hopefully fixed

src/main.lua

@@ -638,26 +638,31 @@ local function VP_createstack(buf, dimensions)
             end
             VP_optimizestack(tempbuf)
 
-            if #tempbuf > 0 then out[posasstring(x,z)] = tempbuf end
+            if #tempbuf > 0 then
+                out[posasstring(x,z)] = tempbuf
+            end
         end
     end
-    for i,v in pairs(out) do print("ok");read() end
+
+
     fout["stacks"] = out
     return fout
 end
+local function VP_lengthofdict(target)
+    local out = 0
+    for _,v in pairs(target) do out = out + 1 end
+    return out
+end
 local function VP_splitstack(_stack, x)
     local stack = _stack["stacks"]
-    if #stack == 0 then
-        error("Internal error, splitstack received 0 stacks. There is nothing to split.")
-    end
     local dimensions = _stack["dimensions"]
     local sx = dimensions["sx"]
     local sz = dimensions["sz"]
     local height = _stack["height"]
     local stacks = {}
     local unevenstack = {}
-    local stackmod = math.fmod(#stack, x)
-    local stackdiv = math.floor(#stack/x)
+    local stackmod = math.fmod(VP_lengthofdict(stack), x)
+    local stackdiv = math.floor(VP_lengthofdict(stack)/x)
 
     if stackmod ~= 0 then
         for tempstackindex=0,stackmod,1 do