Heya, yeap this has happened to me too. Also the prob with saving stuff to the library and it being there but it will not render. I hear long names can be the cause of that one. Not sure what happens to the saved Pz3 file. So I save one file right after another. ver1, ver2, ver3, etc., until I am done. Then I wipe all the ones I don't need and back up the one I want to keep.