My first guess is you either didn't export with 3.1.05 or you aren't using the latest spine-libgdx. I see 3.1.05 in the binary file and that nonessential=false, before loading fails. I can export the raptor example project with nonessential=false and load it using the Skeleton Viewer, but maybe there is something about your project. Possibly you don't use the latest spine-libgdx, you can test using the Skeleton Viewer. It is kept up to date. Otherwise, can you please email the .spine project file? We will keep it confidential and you don't need to include the images. contact@esotericsoftware.com
Fixed in Git!
