It doesn't immediately get messed up.
What I've been doing is importing a pre-rigged model, or even just the skeleton without the model. I can export it It creates the file alright, the original rig stays just fine and I can edit it or export it again.
However when I open the exported file it's all messed up. It opens fine but the bones don't resemble the original. And also I have noticed that the model itself became a bone, so if the model was named "Skeleton" there would be a new bone in the mess named "skeleton"
I think that may be my fault with one of the options, but I don't understand why the original bones get so messed up.
What I've been doing is importing a pre-rigged model, or even just the skeleton without the model. I can export it It creates the file alright, the original rig stays just fine and I can edit it or export it again.
However when I open the exported file it's all messed up. It opens fine but the bones don't resemble the original. And also I have noticed that the model itself became a bone, so if the model was named "Skeleton" there would be a new bone in the mess named "skeleton"
I think that may be my fault with one of the options, but I don't understand why the original bones get so messed up.