I think you can import, but it's tricky. I only tried it once. Imported an ivy from the Ivy Generator... it came into the program, was listed, but the ivy exceded the poly count. It was the only .obj I had available at the time. What you do is copy the obj file to the directory where the other .obj's are at. A restart of the program might be needed, but it wasn't for me. The thing found the ivy by the time I alt-tabbed back to it.