Reaper's mask and Selective channeling
 

Hello,

I set a cleric NPC whith Cha 13 and the feat Selective channeling.

When I give her a skinsaw mask, it's ok. The wearer takes 1 point of Charisma damage, and - attribute damage being not the same as drain - the cleric keeps Charisma 13.

But when she dons a reaper's mask, which inflicts the same Charisma damage as the skinsaw mask, HL lows Charisma to 12 ... and highlights Selective channeling in red, as if it was Charisma drain !

It seems it's a bug ...

Double-check that effect. I don't have the package so can't actually put the masks on a PC, but looking at the items in the editor show BOTH to have the same penalty to CHA scripted.
If you still see differences, you can email support or report the bug.

I reported this bug in HLC over 2 years ago. I'd recommend doing it again. HLC treats ability damage with the same penalties as ability drain.