Daigoro, I had the same problem. The Carrara crash and I lost a model. But, after update the Carrara 3.0 to 3.0.3 I could recover it. Since the update, I never lost any model...but Carrara still crashing like a hell... ^_^!
I agree with Kix, ominousplay. Animals and organics are hard to make in 3D, is a incredible challenge for the artists. I think your model is very good, dont give up.