Potion of Hiding & Potion of Sneaking do nothing?

I think it only bugs out in that direction, but I'm not 100% sure.

Spell IDs work like a serial number, though I think they get reset on map change.

I agree it's not a big deal - though it's probably fixable through TemplePlus (we can change it so it stores and reads the bonus type in the fourth argument). One day...