It appears that when the spine runtime is being used with UE4 any other json content files are treated as if they were SpineSkeletonDataAsset. For example, my current project uses json as a container for some useful text based data, but when I load the editor now I get a series of errors about "failed to import spine skeleton data" for each file. It might make sense for spine to either peek at the json for identifying information or use a different suffix to avoid owning the .json suffix which has wider application than just spine.
