saturation value in f3 shows as NaN, and in the HUD the yellow is gone, as if no longer working

Holding both vanilla food items and modded food items also does not show the saturation bar

My guess is that this is caused by some other mod and you actually currently have NaN saturation (e.g. you ate some food with a NaN saturation modifier or something like that).

I believe the only way this could be caused by AppleSkin itself would be that the syncing of the saturation from server to client is faulty, but that seems pretty unlikely since this is the first of this type of report AppleSkin has ever gotten.

I'll check mod compatibility if something seems off, though everything went fine with the mods present

Created a new world, it now works, definetly a mod compat issue, you can close the thread if you want
edit: although editing the player data from the world folder with an NBTExplorer did not work, the DAT file just duplicates itself

OMMOGGGGG IT WORKED
nbt editing did the job
though the cause of the bug is unknown