Sanctuary – “Crimson Tide” [Campaign 4 – Mission 3]

Good people! Help me! The second building cannot be upgraded; the button is inactive. I can't reach the ships (it won't travel on water), although it can travel along the river to the initial building. I can't talk to the ghost for the same reason! Please tell me what to do? I've been running around the map for two days! I've captured all the buildings (except for the top right orcish one).