DOS party handling;
DOS combat;
DOS surface interactions.

What else is there to an RPG but the environment, party, party movement and combat? The only thing DnD here, is the setting.

I thoroughly loved BG/BG II. I disliked DOS/DOS II. Bought this expecting BG, got DOS. Refunded via STEAM. You apparently were not convinced of the market viabilitry of DOS III, so you hijacked BG to get your DOS III game out. Shame on you.