diff --git a/README.md b/README.md
index d5513e7..9fe4b32 100644
--- a/README.md
+++ b/README.md
@@ -21,6 +21,20 @@ This program comes without any warranty, to the extent permitted by applicable l
     echo "refresh_map_enable:False" > ~/minetest/util/chunkymap-signals.txt
 	sleep 15s
 	echo "loop_enable:False" > ~/minetest/util/chunkymap-signals.txt
+	* list of signals:
+		loop_enable:True
+		loop_enable:False
+		refresh_players_enable:True
+		refresh_players_enable:False
+		refresh_map_enable:True
+		refresh_map_enable:False
+		#rerenders chunks that were rendered in this run:
+		recheck_rendered:True
+		#where 1 is number of seconds:
+		refresh_map_seconds:1
+		#where 1 is number of seconds:
+		refresh_players_seconds:1
+		
 * Has static html version of map (echo_chunkymap_table() php function) -- see example.php
 	* Zoom in and out
 	* optionally echo name of world that was detected by the scheduled py file
@@ -89,6 +103,7 @@ This program comes without any warranty, to the extent permitted by applicable l
     chunkymap-regen-loop.bat
 	* copy example.php and chunkymap.php (and optionally browser.php) to your DocumentRoot or whatever folder will contain the chunkymapdata folder
 ## Known Issues
+* 
 * chunkymap.php should read the size of the chunks -- see near is_file($chunk_genresult_path) in chunkymap.php
 * optionally hide player location
 * Make a method (in chunkymap.php) to echo the map as an html5 canvas (refresh players every 10 seconds, check for new map chunks every minute)
diff --git a/chunkymap-regen.py b/chunkymap-regen.py
index 0eaf38c..f47f7b7 100644
--- a/chunkymap-regen.py
+++ b/chunkymap-regen.py
@@ -789,39 +789,39 @@ class MTChunks:
 
         is_render_needed = False
 
-        #if not self.is_chunk_fresh(chunk_luid):
-        if is_player_in_this_chunk:
-            if self.is_chunk_yaml_marked(chunk_luid):
-                if self.is_chunk_yaml_marked_empty(chunk_luid):
+        if not self.is_chunk_fresh(chunk_luid):
+            if is_player_in_this_chunk:
+                if self.is_chunk_yaml_marked(chunk_luid):
+                    if self.is_chunk_yaml_marked_empty(chunk_luid):
+                        is_render_needed = True
+                        if self.is_verbose:
+                            print (chunk_luid+": RENDERING nonfresh previously marked empty (player in it)")
+                        else:
+                            sys.stdout.write('.')
+                    else:
+                        if self.is_verbose:
+                            print (chunk_luid+": SKIPPING nonfresh previously marked nonempty (player in it)")
+                        #else:
+                            #sys.stdout.write('.')
+                else:
                     is_render_needed = True
                     if self.is_verbose:
-                        print (chunk_luid+": RENDERING nonfresh previously marked empty (player in it)")
+                        print (chunk_luid+": RENDERING nonfresh unmarked (player in it)")
                     else:
                         sys.stdout.write('.')
-                else:
-                    if self.is_verbose:
-                        print (chunk_luid+": SKIPPING nonfresh previously marked nonempty (player in it)")
-                    #else:
-                        #sys.stdout.write('.')
             else:
-                is_render_needed = True
-                if self.is_verbose:
-                    print (chunk_luid+": RENDERING nonfresh unmarked (player in it)")
+                if (not self.is_chunk_yaml_marked(chunk_luid)):
+                    is_render_needed = True
+                    if self.is_verbose:
+                        print (chunk_luid+": RENDERING nonfresh unmarked (simple check since has no player)")
+                    else:
+                        sys.stdout.write('.')
                 else:
-                    sys.stdout.write('.')
+                    if self.is_verbose:
+                        print (chunk_luid+": SKIPPING nonfresh previously marked (simple check since has no player)")
         else:
-            if (not self.is_chunk_yaml_marked(chunk_luid)):
-                is_render_needed = True
-                if self.is_verbose:
-                    print (chunk_luid+": RENDERING nonfresh unmarked (simple check since has no player)")
-                else:
-                    sys.stdout.write('.')
-            else:
-                if self.is_verbose:
-                    print (chunk_luid+": SKIPPING nonfresh previously marked (simple check since has no player)")
-        #else:
-        #    if self.is_verbose:
-        #        print (chunk_luid+": SKIPPING fresh chunk")
+            if self.is_verbose:
+                print (chunk_luid+": SKIPPING fresh chunk")
             #if (not self.is_chunk_yaml_marked(chunk_luid)):
                 #is_render_needed = True
 
@@ -1136,6 +1136,13 @@ class MTChunks:
                                 print("ERROR: expected >=1 seconds for refresh_players_seconds (int or float)")
                         else:
                             print("ERROR: expected int for "+this_key)
+                    elif this_key=="recheck_rendered":
+                        if type(signals[this_key]) is bool:
+                            if signals[this_key]:
+                                for chunk_luid in self.chunks.keys():
+                                    self.chunks[chunk_luid].is_fresh = False
+                        else:
+                            print("ERROR: expected bool for "+this_key)
                     elif this_key=="refresh_map_enable":
                         if type(signals[this_key]) is bool:
                             self.refresh_map_enable = signals[this_key]
diff --git a/install-chunkymap-on-ubuntu.sh b/install-chunkymap-on-ubuntu.sh
index c2978e6..32eccb7 100644
--- a/install-chunkymap-on-ubuntu.sh
+++ b/install-chunkymap-on-ubuntu.sh
@@ -52,7 +52,7 @@ chmod -x "$CHUNKYMAP_DEST/unused/chunkymap-cronjob"
 chmod -x "$CHUNKYMAP_DEST/unused/set-minutely-crontab-job.sh"
 chmod -x "$CHUNKYMAP_DEST/unused/set-minutely-players-crontab-job.sh"
 
-sudo apt-get install python-numpy python-pil
+sudo apt-get install python-numpy python-pil python-leveldb
 echo ""
 echo "To see what needs to be in your $MT_MY_WEBSITE_PATH directory (if you don't use that directory, modify chunkymap-regen.py to use your directory):"
 echo "cd $CHUNKYMAP_DEST/web"