diff --git a/overviewer.py b/overviewer.py
index 08d9948..7f02289 100755
--- a/overviewer.py
+++ b/overviewer.py
@@ -18,25 +18,13 @@
 import platform
 import sys
 
+# quick version check
 if not (sys.version_info[0] == 2 and sys.version_info[1] >= 6):
     print "Sorry, the Overviewer requires at least Python 2.6 to run"
     if sys.version_info[0] >= 3:
         print "and will not run on Python 3.0 or later"
     sys.exit(1)
 
-isBareConsole = False
-
-if platform.system() == 'Windows':
-    try:
-        import ctypes
-        GetConsoleProcessList = ctypes.windll.kernel32.GetConsoleProcessList
-        num = GetConsoleProcessList(ctypes.byref(ctypes.c_int(0)), ctypes.c_int(1))
-        if (num == 1):
-            isBareConsole = True
-
-    except Exception:
-        pass
-
 import os
 import os.path
 import re
@@ -44,110 +32,13 @@ import subprocess
 import multiprocessing
 import time
 import logging
-from overviewer_core import util
-
-def doExit(msg=None, code=1, wait=None, consoleMsg=True):
-    '''Exits Overviewer.  If `wait` is None, the default
-     will be true is 'isBareConsole' is true'''
-    global isBareConsole
-    if msg:
-        print msg
-
-    if wait == None:
-        if isBareConsole:
-            if consoleMsg:
-                print "\n"
-                print "The Overviewer is a console program.  Please open a Windows command prompt"
-                print "first and run Overviewer from there.   Further documentation is available at"
-                print "http://docs.overviewer.org/\n"
-            print "Press [Enter] to close this window."
-            raw_input()
-    else:
-        if wait:
-            if consoleMsg:
-                print "\n"
-                print "The Overviewer is a console program.  Please open a Windows command prompt"
-                print "first and run Overviewer from there.   Further documentation is available at"
-                print "http://docs.overviewer.org/\n"
-            print "Press [Enter] to close this window."
-            raw_input()
-
-    sys.exit(code) 
-
-
-this_dir = util.get_program_path()
-
-# make sure the c_overviewer extension is available
-try:
-    from overviewer_core import c_overviewer
-except ImportError:
-    ## if this is a frozen windows package, the following error messages about
-    ## building the c_overviewer extension are not appropriate
-    if hasattr(sys, "frozen"):
-        print "Something has gone wrong importing the c_overviewer extension.  Please"
-        print "make sure the 2008 and 2010 redistributable packages from Microsoft"
-        print "are installed."
-        doExit()
-
-
-    ## try to find the build extension
-    ext = os.path.join(this_dir, "overviewer_core", "c_overviewer.%s" % ("pyd" if platform.system() == "Windows" else "so"))
-    if os.path.exists(ext):
-        print "Something has gone wrong importing the c_overviewer extension.  Please"
-        print "make sure it is up-to-date (clean and rebuild)"
-        doExit()
-
-    import traceback
-    traceback.print_exc()
-
-    print ""
-    print "You need to compile the c_overviewer module to run Minecraft Overviewer."
-    print "Run `python setup.py build`, or see the README for details."
-    doExit()
-
-from overviewer_core import textures
-
-if hasattr(sys, "frozen"):
-    pass # we don't bother with a compat test since it should always be in sync
-elif "extension_version" in dir(c_overviewer):
-    # check to make sure the binary matches the headers
-    if os.path.exists(os.path.join(this_dir, "overviewer_core", "src", "overviewer.h")):
-        with open(os.path.join(this_dir, "overviewer_core", "src", "overviewer.h")) as f:
-            lines = f.readlines()
-            lines = filter(lambda x: x.startswith("#define OVERVIEWER_EXTENSION_VERSION"), lines)
-            if lines:
-                l = lines[0]
-                if int(l.split()[2].strip()) != c_overviewer.extension_version():
-                    print "Please rebuild your c_overviewer module.  It is out of date!"
-                    doExit(code=1, consoleMsg=True)
-else:
-    print "Please rebuild your c_overviewer module.  It is out of date!"
-    doExit()
-
 from optparse import OptionParser
+
+from overviewer_core import util
+from overviewer_core import textures
 from overviewer_core import optimizeimages, world
-#from overviewer_core import googlemap
 from overviewer_core import configParser, tileset, assetmanager, dispatcher
 
-# definitions of built-in custom modes
-# usually because what used to be a mode became an option
-# for example, night mode
-builtin_custom_rendermodes = {}
-#     'night' : {
-#         'parent' : 'lighting',
-#         'label' : 'Night',
-#         'description' : 'like "lighting", except at night',
-#         'options' : {'night' : True}
-#     },
-
-#     'smooth-night' : {
-#         'parent' : 'smooth-lighting',
-#         'label' : 'Smooth Night',
-#         'description' : 'like "lighting", except smooth and at night',
-#         'options' : {'night' : True}
-#     },
-# }
-
 helptext = """
 %prog [OPTIONS] <World # / Name / Path to World> <tiles dest dir>"""
 
@@ -195,7 +86,6 @@ def configure_logger(loglevel=logging.INFO, verbose=False):
         logger.setLevel(loglevel)
 
 def main():
-
     # bootstrap the logger with defaults
     configure_logger()
 
@@ -216,7 +106,6 @@ def main():
     #parser.add_option("--forcerender", dest="forcerender", help="Force re-rendering the entire map (or the given regionlist). Useful for re-rendering without deleting it.", action="store_true")
     #parser.add_option("--stochastic-render", dest="stochastic_render", help="Rerender a non-updated tile randomly, with the given probability (between 0 and 1). Useful for incrementally updating a map with a new mode.", type="float", advanced=True, default=0.0, metavar="PROBABILITY")
     #parser.add_option("--rendermodes", dest="rendermode", help="Specifies the render types, separated by ',', ':', or '/'. Use --list-rendermodes to list them all.", type="choice", required=True, default=avail_rendermodes[0], listify=True)
-    parser.add_option("--list-rendermodes", dest="list_rendermodes", action="store_true", help="List available render modes and exit.")
     #parser.add_option("--rendermode-options", dest="rendermode_options", default={}, advanced=True, help="Used to specify options for different rendermodes.  Only useful in a settings.py file")
     #parser.add_option("--custom-rendermodes", dest="custom_rendermodes", default={}, advanced=True, help="Used to define custom rendermodes.  Only useful in a settings.py file")
     #parser.add_option("--imgformat", dest="imgformat", help="The image output format to use. Currently supported: png(default), jpg.", advanced=True )
@@ -253,59 +142,54 @@ def main():
                 print "Build machine: %s %s" % (overviewer_version.BUILD_PLATFORM, overviewer_version.BUILD_OS)
         except ImportError:
             print "(build info not found)"
-            pass
-        doExit(code=0, consoleMsg=False)
-
-    # setup c_overviewer rendermode customs / options
-    for mode in builtin_custom_rendermodes:
-        c_overviewer.add_custom_render_mode(mode, builtin_custom_rendermodes[mode])
-    # TODO allow custom rendermodes to be specified in a settings.py file
-    #for mode in options.custom_rendermodes:
-    #    c_overviewer.add_custom_render_mode(mode, options.custom_rendermodes[mode])
-    #for mode in options.rendermode_options:
-    #    c_overviewer.set_render_mode_options(mode, options.rendermode_options[mode])
-    
-    
-    
-    if options.list_rendermodes:
-        list_rendermodes()
-        doExit(code=0, consoleMsg=False)
+        return 0
 
     if options.check_terrain:
         import hashlib
-        from overviewer_core.textures import _find_file
-        if options.textures_path:
-            textures._find_file_local_path = options.textures_path
+        from overviewer_core.textures import Textures
+        # TODO custom textures path?
+        tex = Textures()
 
         try:
-            f = _find_file("terrain.png", verbose=True)
+            f = tex.find_file("terrain.png", verbose=True)
         except IOError:
             logging.error("Could not find the file terrain.png")
-            doExit(code=1, consoleMsg=False)
+            return 1
 
         h = hashlib.sha1()
         h.update(f.read())
         logging.info("Hash of terrain.png file is: `%s`", h.hexdigest())
-        doExit(code=0, consoleMsg=False)
+        return 0
+
+    if options.display_config:
+        # just display the config file and exit
+        parser.display_config()
+        return 0
     
     # TODO remove advanced help?  needs discussion
-    #if options.advanced_help:
-    #    parser.advanced_help()
-    #    doExit(code=0, consoleMsg=False)
-
     # TODO right now, we will not let users specify worlds to render on the command line.  
     # TODO in the future, we need to also let worlds be specified on the command line
 
+    # if no arguments are provided, print out a helpful message
+    if len(args) == 0:
+        # first provide an appropriate error for bare-console users
+        # that don't provide any options
+        if util.is_bare_console():
+            print "\n"
+            print "The Overviewer is a console program.  Please open a Windows command prompt"
+            print "first and run Overviewer from there.   Further documentation is available at"
+            print "http://docs.overviewer.org/\n"
+        else:
+            # more helpful message for users who know what they're doing
+            logging.error("You need to give me your world number or directory")
+            parser.print_help()
+            list_worlds()
+        return 1
+    
     # for multiworld, we must specify the *outputdir* on the command line
-    if len(args) == 1:
+    elif len(args) == 1:
         logging.debug("Using %r as the output_directory", args[0])
         destdir = os.path.expanduser(args[0])
-
-    elif len(args) < 1:
-        logging.error("You need to give me your world number or directory")
-        parser.print_help()
-        list_worlds()
-        doExit(code=1, consoleMsg=True)
     elif len(args) == 2: # TODO support this usecase
         worlddir = os.path.expanduser(args[0])
         destdir = os.path.expanduser(args[1])
@@ -319,14 +203,7 @@ def main():
                     if os.path.exists(" ".join(args[start:end])):
                         logging.warning("It looks like you meant to specify \"%s\" as your world dir or your output\n\
 dir but you forgot to put quotes around the directory, since it contains spaces." % " ".join(args[start:end]))
-                        doExit(code=1, consoleMsg=False)
-
-    
-    if options.display_config:
-        # just display the config file and exit
-        parser.display_config()
-        doExit(code=0, consoleMsg=False)
-
+                        return 1
 
     # TODO regionlists are per-world
     #if options.regionlist:
@@ -363,11 +240,11 @@ dir but you forgot to put quotes around the directory, since it contains spaces.
     #    except IOError as e:
     #        logging.error("Unable to open file %s to use for changelist." % options.changelist)
     #        logging.error("I/O Error: %s" % e.strerror)
-    #        doExit(code=1, consoleMsg=False)
+    #        return 1
 
     #if options.changelist_format != "auto" and not options.changelist:
     #    logging.error("changelist_format specified without changelist.")
-    #    doExit(code=1, consoleMsg=False)
+    #    return 1
     #if options.changelist_format == "auto":
     #    options.changelist_format = "relative"
 
@@ -382,7 +259,7 @@ dir but you forgot to put quotes around the directory, since it contains spaces.
         tex.generate()
     except IOError, e:
         logging.error(str(e))
-        doExit(code=1, consoleMsg=False)
+        return 1
 
     # look at our settings.py file
     mw_parser = configParser.MultiWorldParser("settings.py")
@@ -429,127 +306,7 @@ dir but you forgot to put quotes around the directory, since it contains spaces.
     dispatch.close()
 
     assetMrg.finalize(tilesets)
-
-    sys.exit("early abort")
- 
-    # First do world-level preprocessing. This scans the world hierarchy, reads
-    # in the region files and caches chunk modified times, and determines the
-    # chunk bounds (max and min in both dimensions)
-    w = world.World(worlddir)
-    rset = w.get_regionsets()[0] # use the default
-    if north_direction == 'auto':
-        # TODO get this from the asset manager # north_direction = w.persistentData['north_direction']
-        options.north_direction = north_direction
-
-    # TODO deal with changed north direction
-    
-    # A couple other things we need to figure out about the world:
-    w.get_regionsets()[0].determine_bounds()
-    # w.find_true_spawn()
-
-    logging.info("Rendering the following tilesets: %s", ",".join(options.rendermode))
-
-    bgcolor = (int(options.bg_color[1:3],16),
-               int(options.bg_color[3:5],16),
-               int(options.bg_color[5:7],16),
-               0)
-
-    # Create the quadtrees. There is one quadtree per rendermode requested, and
-    # therefore, per output directory hierarchy of tiles. Each quadtree
-    # individually computes its depth and size. The constructor computes the
-    # depth of the tree, while the go() method re-arranges tiles if the current
-    # depth differs from the computed depth.
-    q = []
-    qtree_args = {'depth' : options.zoom,
-                  'imgformat' : imgformat,
-                  'imgquality' : options.imgquality,
-                  'optimizeimg' : optimizeimg,
-                  'bgcolor' : bgcolor,
-                  'forcerender' : options.forcerender,
-                  'rerender_prob' : options.stochastic_render
-                  }
-    for rendermode in options.rendermode:
-        if rendermode == 'normal':
-            qtree = quadtree.QuadtreeGen(rset, destdir, rendermode=rendermode, tiledir='tiles', **qtree_args)
-        else:
-            qtree = quadtree.QuadtreeGen(rset, destdir, rendermode=rendermode, **qtree_args)
-        q.append(qtree)
-    
-    # Make sure the quadtrees are the correct depth
-    for qtree in q:
-        qtree.check_depth()
-
-    # create the distributed render
-    r = rendernode.RenderNode(q, options)
-    # for the pool_initializer
-    r.builtin_custom_rendermodes = builtin_custom_rendermodes
-    
-    # write out the map and web assets
-    m = googlemap.MapGen(q, configInfo=options)
-    m.go(options.procs)
-    
-    # render the tiles!
-    r.go(options.procs)
-
-    # finish up the map
-    m.finalize()
-
-    if options.changelist:
-        changed=[]
-        for tile in r.rendered_tiles:
-            if options.changelist_format=="absolute":
-                tile=os.path.abspath(tile)
-            changed.append(tile)
-            for zl in range(q[0].p - 1):
-                tile=os.path.dirname(tile)
-                changed.append("%s.%s" % (tile, imgformat))
-        #Quick and nasty way to remove duplicate entries
-        changed=list(set(changed))
-        changed.sort()
-        for path in changed:
-            changefile.write("%s\n" % path)
-        changefile.close()
-
-def list_rendermodes():
-    "Prints out a pretty list of supported rendermodes"
-    
-    def print_mode_tree(line_max, mode, prefix='', last=False):
-        "Prints out a mode tree for the given mode, with an indent."
-        
-        try:
-            info = c_overviewer.get_render_mode_info(mode)
-        except ValueError:
-            info = {}
-        
-        print prefix + '+-',  mode,
-        
-        if 'description' in info:
-            print " " * (line_max - len(prefix) - len(mode) - 2),
-            print info['description']
-        else:
-            print
-        
-        children = c_overviewer.get_render_mode_children(mode)
-        for child in children:
-            child_last = (child == children[-1])
-            if last:
-                child_prefix = '  '
-            else:
-                child_prefix = '| '
-            print_mode_tree(line_max, child, prefix=prefix + child_prefix, last=child_last)
-    
-    avail_rendermodes = c_overviewer.get_render_modes()
-    line_lengths = {}
-    parent_modes = []
-    for mode in avail_rendermodes:
-        inherit = c_overviewer.get_render_mode_inheritance(mode)
-        if not inherit[0] in parent_modes:
-            parent_modes.append(inherit[0])
-        line_lengths[mode] = 2 * len(inherit) + 1 + len(mode)
-    
-    line_length = max(line_lengths.values())
-    for mode in parent_modes:
-        print_mode_tree(line_length, mode, last=(mode == parent_modes[-1]))
+    return 0
 
 def list_worlds():
     "Prints out a brief summary of saves found in the default directory"
@@ -582,18 +339,14 @@ def list_worlds():
         size = "%.2fMB" % (info['SizeOnDisk'] / 1024. / 1024.)
         print formatString % (name, size, playstamp, timestamp)
 
-
 if __name__ == "__main__":
     multiprocessing.freeze_support()
     try:
-        main()
+        ret = main()
+        util.exit(ret)
     except Exception, e:
-        print e
-        if e.args[0] == "Exiting":
-            logging.info("Exiting...")
-            doExit(code=0, wait=False)
         logging.exception("""An error has occurred. This may be a bug. Please let us know!
 See http://docs.overviewer.org/en/latest/index.html#help
 
 This is the error that occurred:""")
-        doExit(code=1, consoleMsg=False)
+        util.exit(1)
diff --git a/overviewer_core/__init__.py b/overviewer_core/__init__.py
index e69de29..ec4081e 100644
--- a/overviewer_core/__init__.py
+++ b/overviewer_core/__init__.py
@@ -0,0 +1,71 @@
+#
+# Code to check to make sure c_overviewer is built and working
+#
+
+import os.path
+import platform
+import traceback
+import sys
+
+import util
+
+def check_c_overviewer():
+    """Check to make sure c_overviewer works and is up-to-date. Prints
+    out a helpful error and returns 1 if something's wrong, returns 0
+    otherwise.
+    """
+    root_dir = util.get_program_path()
+    # make sure the c_overviewer extension is available
+    try:
+        import c_overviewer
+    except ImportError:
+        ## if this is a frozen windows package, the following error messages about
+        ## building the c_overviewer extension are not appropriate
+        if hasattr(sys, "frozen") and platform.system() == 'Windows':
+            print "Something has gone wrong importing the c_overviewer extension.  Please"
+            print "make sure the 2008 and 2010 redistributable packages from Microsoft"
+            print "are installed."
+            return 1
+
+        ## try to find the build extension
+        ext = os.path.join(root_dir, "overviewer_core", "c_overviewer.%s" % ("pyd" if platform.system() == "Windows" else "so"))
+        if os.path.exists(ext):
+            traceback.print_exc()
+            print ""
+            print "Something has gone wrong importing the c_overviewer extension.  Please"
+            print "make sure it is up-to-date (clean and rebuild)"
+            return 1
+
+        print "You need to compile the c_overviewer module to run Minecraft Overviewer."
+        print "Run `python setup.py build`, or see the README for details."
+        return 1
+
+    #
+    # make sure it's up-to-date
+    #
+
+    if hasattr(sys, "frozen"):
+        pass # we don't bother with a compat test since it should always be in sync
+    elif "extension_version" in dir(c_overviewer):
+        # check to make sure the binary matches the headers
+        if os.path.exists(os.path.join(root_dir, "overviewer_core", "src", "overviewer.h")):
+            with open(os.path.join(root_dir, "overviewer_core", "src", "overviewer.h")) as f:
+                lines = f.readlines()
+                lines = filter(lambda x: x.startswith("#define OVERVIEWER_EXTENSION_VERSION"), lines)
+                if lines:
+                    l = lines[0]
+                    if int(l.split()[2].strip()) != c_overviewer.extension_version():
+                        print "Please rebuild your c_overviewer module.  It is out of date!"
+                        return 1
+    else:
+        print "Please rebuild your c_overviewer module.  It is out of date!"
+        return 1
+    
+    # all good!
+    return 0
+
+# only check the module if we're not setup.py
+if not sys.argv[0].endswith("setup.py"):
+    ret = check_c_overviewer()
+    if ret > 0:
+        util.exit(ret)
diff --git a/overviewer_core/util.py b/overviewer_core/util.py
index 156d4de..3f09b4c 100644
--- a/overviewer_core/util.py
+++ b/overviewer_core/util.py
@@ -21,6 +21,7 @@ import imp
 import os
 import os.path
 import sys
+import platform
 from subprocess import Popen, PIPE
 import logging
 from cStringIO import StringIO
@@ -88,6 +89,33 @@ def findGitVersion():
         except Exception:
             return "unknown"
 
+def is_bare_console():
+    """Returns true if Overviewer is running in a bare console in
+    Windows, that is, if overviewer wasn't started in a cmd.exe
+    session.
+    """
+    if platform.system() == 'Windows':
+        try:
+            import ctypes
+            GetConsoleProcessList = ctypes.windll.kernel32.GetConsoleProcessList
+            num = GetConsoleProcessList(ctypes.byref(ctypes.c_int(0)), ctypes.c_int(1))
+            if (num == 1):
+                return True
+                
+        except Exception:
+            pass
+    return False
+
+def exit(ret=0):
+    """Drop-in replacement for sys.exit that will automatically detect
+    bare consoles and wait for user input before closing.
+    """
+    if ret and is_bare_console():
+        print
+        print "Press [Enter] to close this window."
+        raw_input()
+    sys.exit(ret)
+
 # http://docs.python.org/library/itertools.html
 def roundrobin(iterables):
     "roundrobin('ABC', 'D', 'EF') --> A D E B F C"