hi, I guess it's a bit weird of a system, but if you build the dwarves, it will also unlock the tavern. Basically building one dwelling in an exclusive pair will also clear requirements of the other one! You're right, if that weren't the case, it'd suck. I wonder how I can explain the mechanic better tho...
oh ok, I think the way to do it would be either drawing a line from both to the tavern, or by having both not have lines anywhere, maybe positioned next to each other with an OR symbol between. games coming along well, seems more balanced. I did notice some bugs with the digging quests, they can keep going forever while being in the same general location, I had one hero successfully digging every 2 turns for maybe 16 turns in a row until the dig site bugged to a undiggable location.