Could be that M1 is not supported with the Spine Plugin?
However, Illustrator to Spine has not been updated for about 4 years, so there is a possibility that we should update something for newer Illustrator versions. I'd like to make an issue ticket on github, so could you tell me what version of Illustrator you are using?
Also, have you tried to use PhotoshopToSpine via
File - Scripts - Other Scripts - Choose jsx file?
Thank you for your reporting, we reproduced the bug and I made an issue ticket for this problem:
However, if I delete the layer group that using [folder] tag, it can be exported. Also, the exported files can be imported to Spine Editor without any problem. Therefore, could you send us the PSD that the problem occurred via email ( firstname.lastname@example.org)? We'd like to verify the PSD.