While i dont know of any official way to do it, what you may want to do is make the first part of your animation, save it, and then start a new one. Load your previous part, clear the animation frames, and start from that point. The reason your getting an error is probably thanks to one of Carrara's thousands of glitches. You could also try saving the last frame, then start a new animation, and use the merge feature to continue on with your animation. Good Luck! Your pic looks great so far. Cant wait to see the finished result.