How are we supposed to improve upon a character and their animations when exporting to software like Unreal or elsewhere?

I made a character in character creator, made 5 animations in iclone 7 for said character and used 3dxchange to import into Unreal Engine. 
In total I saved the 5 animations and the avatar as both iclone files and fbx. 12 files total.

After testing everything in unreal I figured I had to go back and add some collision and cloth changes to the character.

No problem, I went back into iclone 7 with the same character, changed the cloth, added weight maps, collision boxes and breast springs.

Now here comes the issue. Even though I saved all the animations/facial gestures I had made with the same character, I have not been able to rerig them to the updated character.

For starters the updated character's FBX file does not work with the animation FBX files in unreal.

More importantly, the animations are not detected when imported to the FBX of the updated character in 3dxchange. The animations will not sync to the Avatar in iClone 7 when sending animations through 3dxchange into iClone.

How in the world am I going to make progress now and in the future without the ability to reuse animations I made.

Is this a known thing? That you can't go back to and edit characters or previously made animations or you lose all your animation work for that character?

How can I going to go back and edit the animations and build upon them? This seems like a joke. I thought there was supposed to be compatibility!!!!