I loaded Core and Bestiary. Created new character and clicked Create Monster. Selected Devil (Imp).
Things To Be Done section lists "Select a bonus language." But when I click "Add Bonus Language" the popup shows Languages Remaining 1...but does not list any languages in the left-hand pane.
Or maybe it’s a bug in both the race definition and the kit. Currently the race includes AUTO:LANG|Common|Infernal. Maybe instead race should include both AUTO:LANG|Infernal and LANGBONUS:ALL. Then have the kit add the tag LANGBONUS:Common to assign the one INT-based bonus language.
Fixed in PR #6084