For Haer-dalis, you can only get the playhouse if your Charname is also a bard, wich is indeed a bug.
For the ranger stronghold you can go to the temple ruins inmediately after getting the cabin and rest there, Mairyn appears and talking to her will spawn the Thombelten party twice but can be finisheable that way.
I don't know how the rest of the mod plays cause im still early in the game but yeah, hopefully it'll get better