I have run into this problem myself a few times, in unmodded galciv games. I am quite confident that your mod is not the problem, something can go wrong if you zoom and move at the same time. After trying extensively to counter this annoying behaviour, I eventually found that if I moved a particular ship, the problem would disappear. I seem to recall it locks up with a planned move (much like the "turn" button getting stuck), but it might also be a ship you can find through hitting "next". Move that ship and the motionsickness stops. It's been too long since I ran into the problem to give you any more specific advice, but "look for the ship" should be enough of a tip to help you figure it out on your own. Good luck!