Hello, I'm sorry to hear that you're encountering issues exporting from Spine.
Are you clicking on Texture Atlas: Pack when you are trying to obtain the texture atlas and PNG on export?
Spine will only generate your JSON (but not the atlas or PNG) if Pack is left unchecked.
If you check Pack, the texture atlas (ending in .atlas) and the PNG will be output along with your JSON.
More info about exporting can be found here: Export - Spine User Guide
