If it loads in to Milkshape then export it as a GameSpace model from there and then load it into GameSpace it's self. Only edit GameSpace models in GameSpace and then export them to your required format using a different filename.
GameSpace isn't the first program to crash because of "bad geometry" and it isn't the worst (nor the best). In my opinion it's usally a result of incompatability in the import/exporters of the the programs that created the model and the one your trying to load it in to.
GameSpace isn't the first program to crash because of "bad geometry" and it isn't the worst (nor the best). In my opinion it's usally a result of incompatability in the import/exporters of the the programs that created the model and the one your trying to load it in to.