The problem I'm having are server hosts that auto-update mods. They keep auto "upgrading" hyarion from .24 to .25 then throwing errors on startup as it doesnt work on 2.1
Not sure if it's the same issue as the original poster's.
Now the 2.1 is stable hyarion will stop receiving 2.0 updates so this will stop happening, also when a mod version is marked as 2.0 it doesn't appear in 2.1 and vice versa so it shouldn't be available tot he auto updater
