Sent.
I got around this by using F11 -> F7 and moving onto the next quest line. I just want to be able to capture cities for myself and Spain. I really am not interested in any n nation quests or important quests. Though even though I finished the quest to capture La Vega and have an option in the Governor-general dialog to give a city to Spain, the game still did not let me capture Port Royale though - the governor had no dialogue option to take over the city for myself when I took the town. Does it require completing the 'kill the beggars quest or something? Or Port Royale just cant be captured?