Missing mesh filter

Hi,
I'm running the latest Unity Pro version and have just downloaded the Dec5 update of GameDraw.
When I (for instance) create a new mesh using the Boolean option in GameDraw (like cutting out windows and doors for a wall), the inspector shows a mesh (say wall_front) but in the Mesh List there is no such mesh. So when I copy-and-paste the object to another scene, I get the error of a Missing Mesh.
The meshes do show alright, and I can further edit them okay, but apparently the newly created mesh is not really saved?

This also prevents me (I think) of create a prefab of a whole bunch of objects (under 1 parent) that contains several boolean created objects.

Any ideas how to get the meshes to actually be saved?

Marco