When attempting to load a world, I got a message about corrupted datapacks. This happened for every world I had. It offered a safe mode, but that wouldn't load either.

After downgrading to 1.3.4, I was able to load all of the worlds again.

Issue has been found and fixed, will be released alongside some minor technical changes soon.

Have a similar issue on fabric. Not sure if its the same issue effecting the fabric 1.20.1 version of 1.3.5

Fabric was affected by the same issue, both platforms have been fixed in the 1.3.7 release.

This error is now in screen
File lithostitched-forge-1.20.1-1.3.7.jar is not a valid mod file.

This error is now in screen File lithostitched-forge-1.20.1-1.3.7.jar is not a valid mod file.

Having the same problem here

Reupload going out now. I hate forge.