We would need to see the crash log to know if the crash is because the binary file is the wrong version. You need a Skeleton Viewer with the same major and minor version (eg 4.0) as the binary file.

Old atlas files can be read by any version Spine runtime. New atlas files can only be read by version 4.0+. New atlas files can be identified because they don't have indentation.

The first 8 bytes of the binary are a hash, after that is the version as a string stored as a varint then the characters. There is code to read this in the SkeletonBinary class in every runtime.

You can see the version with a hex editor:

Изображение удалено из-за отсутствия поддержки HTTPS. | Показать

You can also likely see the version with a text editor, amongst many unreadable characters.

You picked a JSON file action.json but from this error message:

Error parsing JSON on line 1 near: �mt�Q��'S2P�T{��/d?��3��M�����TERROR,�gt�Y��m����Fg�00'H{�,ouUGwPz���찟Y�����M�o�M���'�e�8��

That doesn't look like JSON data. Open the JSON file in a text editor, it should be readable. If you post or email (contact@esotericsoftware.com) the file, we can help.

Old versions of the Skeleton Viewer aren't provided. You would need to run it from source.

The trial is always the latest version, old versions aren't provided.

The easiest solution would be to use a full version of Spine. If you aren't sure you want to purchase Spine, you can post or email the file and we can save it as a Spine project file so you can view it in the latest trial.