在导出过程中遇到错误时，通常建议检查您使用的Spine版本是否是最新的。根据您提供的信息，您在使用4.3版本导出到4.2时遇到了问题。请确保您使用的是最新的Spine版本，因为较新的版本通常包含错误修复和改进。如果问题仍然存在，您可以尝试将项目文件发送到 contact@esotericsoftware.com，以便团队能够帮助您解决问题。

yugutou Thanks for reporting the issues! I was able to reproduce the first issue you reported, where the version number in the JSON file is incorrect when exporting an older version in JSON format from 4.3-beta. We will fix this in a future release.

Regarding the second issue, is it correct that you are saying that there is no FPS drop in setup mode, but there is a FPS drop in animate mode? This may be the result of improvements made to the curve adjustment, and the increased processing required when changing key values may be leading to drops in FPS.
If you don’t mind, could you please send us your Spine project via email so that we can test it?: contact@esotericsoftware.com
If the issue can be reproduced without an image, you only need to submit the Spine project file.

yugutou Thank you for your email! We have confirmed that we can reproduce the issue using the project you provided.

I forgot to mention this in my previous reply, but when sending an email, please include a brief description in the body explaining how it relates to the specific thread. This ensures clarity, as your email may be read by the entire Spine team, not just me.
We will investigate ways to improve the FPS drop issue.

Your project has 638 physics constraints, 778 bones, and it clips 13,966 triangles. That is a lot to do in one skeleton, and the clipping is especially performance heavy. You may have trouble putting this in a game if you are exporting data. It's OK if you are exporting images/video.

It is slow because auto key is checking everything to see if anything needs to be keyed, and there is a lot to check. We've improved this to be more efficient in 4.3.13-beta. If you turn off auto key, it is much faster, and then you can key with K for Key Edited, which keys everything that is edited. That's the same thing auto key does, but pressing it once after rotating the bone is faster than doing it many times as you rotate.

Also turning off clipping will improve your FPS. You could consider masking with a large image instead (uncheck Export and Select for that image). If exporting images/video you can specify the crop position and size, so you don't need clipping. If exporting data, at runtime you can mask or allow the parts you don't want shown to be drawn off screen.