It seems whenever I set the AV to be added to something that has a different in-game name than script name (examples include archery/marksman and speech/speechcraft, and also values which I've renamed for the purposes of my mod) it seems to break the CK in some way: I set the value to lockpicking (which I've replaced with the in-game name of "thievery") then hit "okay". The perk entries window now shows the relevant entry but under "data 3" it shows the in-game name "thievery" instead of the script name "lockpicking." Then if I go to open it to alter it further I get an error message saying it couldn't find an AV called "thievery" and it resets the value to "AbsorbChance" (the first option alphabetically.)

I haven't tested this in-game yet to see if it works or not. It may simply be an error with the CK, and once I get into the actual game it functions fine. Anyway, thought I'd go ahead and see if anyone else has played with this and if there's a good workaround in case this bug breaks the function.

Well, this appears to simply be an error in the CK. The perk works as intended ingame. The bug makes it mildly annoying to edit the perk, but that's all.