Freeing a copied entity

I would *guess* that a count is kept of all entities that reference a mesh. Copying an entity that points to a given mesh would increment the count and freeing an entity that points to this mesh would decrement the count. When the count is zero the mesh is freed? In any event I doubt thats the cause of the problem (unless you are not freeing all the copies after you are finished with them). Its not something I have come across anyway. If memory were being chewed up its my experience that every starts running slower and slower. If thats the case then you do have a memory leak somewhere, perhaps you are not freeing a pivot or have a runaway type list.