ssssp I downloaded and checked the attached .zip file, and indeed, opening the .spine project and importing the .json file did not work. I looked at the spine.log file and found the following log, so I edited the .json file directly to remove the clipping attachment and was able to open it.
java.lang.IllegalArgumentException: No enum constant lk.clipping
Here is the Spine project that you can now open:
I am not sure what the clipping attachment originally did, but I think I have restored most of it with it, so check it out.
