Error when trying to save fxsxml in Nexus B

[AfricanManBeast]

I'm working on a 3d model with new animations but now I wanted to test to see if it'll work in game with the civ 5 animations already present. However, whenever I try to save the fxsxml file I get this error

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I've been trying to see if I could solve it but I have no idea what this means since I had tried to assign the already present civ animations to my model. Does this mean that I have to have animations already present int he gr2 file, despite the fact that I first started off the model as an fbx? Any help would be appreciated.