Make sure the barracks is giving only 15.
I would guess is it is using both the default 15 xp per, plus the 10 on barracks and 20 on armory that are intended. The vanilla game does 15 xp in a domain specific way and this isn't being changed yet by the mod to be zero'd out or set as general XP that can be updated the way the mod used to do in GEM. It then adds 10 for barracks, 20 for armories, which is going on top of the existing bonus.