When you say Free Version do you Mean Bryce 7 Personal Learning edition or Do you mean Bryce 7.1 Pro? Because the Personal Learning Edition version does not let you animate(or so I have been told) if you delete Bryce 7 PLE assuming you use it then install either Bryce 7.1 Pro or use another version of Bryce. Back up your work and once you save a .br7 file it will not work in lower version of bryce. it will keep saying this message in an endless loop. An object is missing Continue loading without it. and it will not stop unless you force quit bryce.

I would try Reinstalling Bryce Completely get rid of 7 PLE and 7 Pro if you have them and then do a fresh install of the program. I hope that helps a bit (I am not sure of the problem but it might be an idea to do a fresh installation)

Karl