Fix Region.generatePrototypeData

BauSystem_Main/src/de/steamwar/bausystem/region/Region.java

@@ -90,7 +90,7 @@ public class Region {
             return;
         }
 
-        if (!prototypes.contains(prototype)) {
+        if (this.prototype != null && !prototypes.contains(prototype)) {
             return;
         }
         this.prototype = prototype;