diff --git a/overviewer_core/quadtree.py b/overviewer_core/quadtree.py
index 36978f2..114fa8b 100644
--- a/overviewer_core/quadtree.py
+++ b/overviewer_core/quadtree.py
@@ -439,9 +439,12 @@ class QuadtreeGen(object):
                     needs_rerender = True
                     break
                 
-                # check region file mtime first. 
-                if regionMtime <= tile_mtime:
-                    continue
+                # check region file mtime first.
+                # on windows (and possibly elsewhere) minecraft won't update
+                # the region file mtime until after shutdown.
+                # for servers this is unacceptable, so skip this check.
+                #if regionMtime <= tile_mtime:
+                #    continue
                
                 # checking chunk mtime
                 if region.get_chunk_timestamp(chunkx, chunky) > tile_mtime:
diff --git a/overviewer_core/src/iterate.c b/overviewer_core/src/iterate.c
index 041f0b4..545f14f 100644
--- a/overviewer_core/src/iterate.c
+++ b/overviewer_core/src/iterate.c
@@ -193,7 +193,7 @@ generate_pseudo_data(RenderState *state, unsigned char ancilData) {
         unsigned char above_level_data = 0, same_level_data = 0, below_level_data = 0, possibly_connected = 0, final_data = 0;
 
         /* check for air in z+1, no air = no connection with upper level */        
-        if ((z != 127) && (getArrayByte3D(state->left_blocks, x, y, z) == 0)) { 
+        if ((z != 127) && (getArrayByte3D(state->blocks, x, y, z + 1) == 0)) { 
             above_level_data = check_adjacent_blocks(state, x, y, z + 1, state->block);
         }   /* else above_level_data = 0 */