diff --git a/includes/luaconsole.h b/includes/luaconsole.h
index fc5e2c436..e55948269 100644
--- a/includes/luaconsole.h
+++ b/includes/luaconsole.h
@@ -19,6 +19,11 @@
 #define LUACON_KDOWN 1
 #define LUACON_KUP 2
 
+//Bitmasks for things that might need recalculating after changes to tpt.el
+#define LUACON_EL_MODIFIED_CANMOVE 0x1
+#define LUACON_EL_MODIFIED_GRAPHICS 0x2
+#define LUACON_EL_MODIFIED_MENUS 0x4
+
 int *lua_el_func, *lua_el_mode;
 
 void luacon_open();
@@ -39,7 +44,7 @@ int luacon_transitionread(lua_State* l);
 int luacon_transitionwrite(lua_State* l);
 int luacon_particle_getproperty(char * key, int * format);
 int luacon_transition_getproperty(char * key, int * format);
-int luacon_element_getproperty(char * key, int * format);
+int luacon_element_getproperty(char * key, int * format, unsigned int * modified_stuff);
 int process_command_lua(pixel *vid_buf, char *console, char *console_error);
 
 int getPartIndex_curIdx;
diff --git a/src/elements/bang.c b/src/elements/bang.c
index 2c5c90408..9a374c2d8 100644
--- a/src/elements/bang.c
+++ b/src/elements/bang.c
@@ -45,12 +45,12 @@ int update_BANG(UPDATE_FUNC_ARGS) {
 			if(!(rand()%2))
 			{
 				create_part(i, x, y, PT_FIRE);
-				parts[i].temp = (MAX_TEMP/4)+otemp;
+				parts[i].temp = restrict_flt((MAX_TEMP/4)+otemp, MIN_TEMP, MAX_TEMP);
 			}
 			else
 			{
 				create_part(i, x, y, PT_SMKE);
-				parts[i].temp = (MAX_TEMP/4)+otemp;
+				parts[i].temp = restrict_flt((MAX_TEMP/4)+otemp, MIN_TEMP, MAX_TEMP);
 			}
 		}
 		else
@@ -60,7 +60,7 @@ int update_BANG(UPDATE_FUNC_ARGS) {
 				create_part(i, x, y, PT_BOMB);
 				parts[i].tmp = 1;
 				parts[i].life = 50;
-				parts[i].temp = (MAX_TEMP/3)+otemp;
+				parts[i].temp = restrict_flt((MAX_TEMP/3)+otemp, MIN_TEMP, MAX_TEMP);
 				parts[i].vx = rand()%20-10;
 				parts[i].vy = rand()%20-10;
 			}
diff --git a/src/elements/ignt.c b/src/elements/ignt.c
index c11fccf95..f002e2dbd 100644
--- a/src/elements/ignt.c
+++ b/src/elements/ignt.c
@@ -31,7 +31,7 @@ int update_IGNT(UPDATE_FUNC_ARGS) {
 				parts[nb].life = 30;
 				parts[nb].vx = rand()%20-10;
 				parts[nb].vy = rand()%20-10;
-				parts[nb].temp = 400.0f+parts[i].temp-273.15;
+				parts[nb].temp = restrict_flt(400.0f+parts[i].temp-273.15, MIN_TEMP, MAX_TEMP);
 			}
 		}
 		else
diff --git a/src/interface.c b/src/interface.c
index bb34c15f1..858af23f3 100644
--- a/src/interface.c
+++ b/src/interface.c
@@ -93,11 +93,18 @@ int drawgrav_enable = 0;
 void menu_count(void)//puts the number of elements in each section into .itemcount
 {
 	int i=0;
+	for (i=0;i<SC_TOTAL;i++)
+	{
+		msections[i].itemcount = 0;
+	}
 	msections[SC_LIFE].itemcount = NGOLALT;
 	msections[SC_WALL].itemcount = UI_WALLCOUNT-4;
 	for (i=0; i<PT_NUM; i++)
 	{
-		msections[ptypes[i].menusection].itemcount+=ptypes[i].menu;
+		if (ptypes[i].menusection<SC_TOTAL)
+		{
+			msections[ptypes[i].menusection].itemcount+=ptypes[i].menu;
+		}
 	}
 
 }
diff --git a/src/luaconsole.c b/src/luaconsole.c
index e7632dd6c..65bda4dac 100644
--- a/src/luaconsole.c
+++ b/src/luaconsole.c
@@ -431,7 +431,7 @@ int luacon_transitionwrite(lua_State* l){
 	}
 	return 0;
 }
-int luacon_element_getproperty(char * key, int * format)
+int luacon_element_getproperty(char * key, int * format, unsigned int * modified_stuff)
 {
 	int offset;
 	if (strcmp(key, "name")==0){
@@ -441,10 +441,14 @@ int luacon_element_getproperty(char * key, int * format)
 	else if (strcmp(key, "color")==0){
 		offset = offsetof(part_type, pcolors);
 		*format = 0;
+		if (modified_stuff)
+			*modified_stuff |= LUACON_EL_MODIFIED_GRAPHICS;
 	}
 	else if (strcmp(key, "colour")==0){
 		offset = offsetof(part_type, pcolors);
 		*format = 0;
+		if (modified_stuff)
+			*modified_stuff |= LUACON_EL_MODIFIED_GRAPHICS;
 	}
 	else if (strcmp(key, "advection")==0){
 		offset = offsetof(part_type, advection);
@@ -501,6 +505,8 @@ int luacon_element_getproperty(char * key, int * format)
 	else if (strcmp(key, "menu")==0){
 		offset = offsetof(part_type, menu);
 		*format = 0;
+		if (modified_stuff)
+			*modified_stuff |= LUACON_EL_MODIFIED_MENUS;
 	}
 	else if (strcmp(key, "enabled")==0){
 		offset = offsetof(part_type, enabled);
@@ -509,10 +515,14 @@ int luacon_element_getproperty(char * key, int * format)
 	else if (strcmp(key, "weight")==0){
 		offset = offsetof(part_type, weight);
 		*format = 0;
+		if (modified_stuff)
+			*modified_stuff |= LUACON_EL_MODIFIED_CANMOVE;
 	}
 	else if (strcmp(key, "menusection")==0){
 		offset = offsetof(part_type, menusection);
 		*format = 0;
+		if (modified_stuff)
+			*modified_stuff |= LUACON_EL_MODIFIED_MENUS;
 	}
 	else if (strcmp(key, "heat")==0){
 		offset = offsetof(part_type, heat);
@@ -529,6 +539,8 @@ int luacon_element_getproperty(char * key, int * format)
 	else if (strcmp(key, "properties")==0){
 		offset = offsetof(part_type, properties);
 		*format = 0;
+		if (modified_stuff)
+			*modified_stuff |= LUACON_EL_MODIFIED_GRAPHICS | LUACON_EL_MODIFIED_CANMOVE;
 	}
 	else if (strcmp(key, "description")==0){
 		offset = offsetof(part_type, descs);
@@ -546,7 +558,7 @@ int luacon_elementread(lua_State* l){
 	float tempfloat;
 	int i;
 	char * key = mystrdup(luaL_optstring(l, 2, ""));
-	offset = luacon_element_getproperty(key, &format);
+	offset = luacon_element_getproperty(key, &format, NULL);
 	free(key);
 	
 	//Get Raw Index value for element
@@ -588,8 +600,9 @@ int luacon_elementwrite(lua_State* l){
 	int tempinteger;
 	float tempfloat;
 	int i;
+	unsigned int modified_stuff = 0;
 	char * key = mystrdup(luaL_optstring(l, 2, ""));
-	offset = luacon_element_getproperty(key, &format);
+	offset = luacon_element_getproperty(key, &format, &modified_stuff);
 	
 	//Get Raw Index value for element
 	lua_pushstring(l, "id");
@@ -640,6 +653,15 @@ int luacon_elementwrite(lua_State* l){
 		*((unsigned char*)(((void*)&ptypes[i])+offset)) = luaL_optinteger(l, 3, 0);
 		break;
 	}
+	if (modified_stuff)
+	{
+		if (modified_stuff & LUACON_EL_MODIFIED_MENUS)
+			menu_count();
+		if (modified_stuff & LUACON_EL_MODIFIED_CANMOVE)
+			init_can_move();
+		if (modified_stuff & LUACON_EL_MODIFIED_GRAPHICS)
+			memset(graphicscache, 0, sizeof(gcache_item)*PT_NUM);
+	}
 	free(key);
 	return 0;
 }
diff --git a/src/main.c b/src/main.c
index a835e3e72..5abc139ab 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1014,7 +1014,7 @@ int main(int argc, char *argv[])
 		
 		gravity_update_async(); //Check for updated velocity maps from gravity thread
 		if (!sys_pause||framerender) //Only update if not paused
-			memset(gravmap, 0, sizeof(gravmap)); //Clear the old gravmap
+			memset(gravmap, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float)); //Clear the old gravmap
 
 		if (framerender) {
 			framerender = 0;
@@ -2258,8 +2258,7 @@ int main(int argc, char *argv[])
 					if (!bq)
 						add_sign_ui(vid_buf, x, y);
 				}
-
-				if (c==PT_FIGH)
+				else if (c==PT_FIGH)
 				{
 					if (!bq)
 						create_part(-1, x, y, PT_FIGH);
diff --git a/src/powder.c b/src/powder.c
index 4acd33404..ca629cf5f 100644
--- a/src/powder.c
+++ b/src/powder.c
@@ -2940,7 +2940,7 @@ int create_parts(int x, int y, int rx, int ry, int c, int flags)
 	{
 		if (wall==r)
 		{
-			if (c == SPC_AIR || c == SPC_HEAT || c == SPC_COOL || c == SPC_VACUUM || c == SPC_PGRV || c == SPC_NGRV)
+			if (c == SPC_AIR || c == SPC_HEAT || c == SPC_COOL || c == SPC_VACUUM || c == SPC_PGRV || c == SPC_NGRV || wall == WL_SIGN)
 				break;
 			if (wall == WL_ERASE)
 				b = 0;