Trade Ship bug?
I was playing around with the tech tree and was checking out resource extraction (I think that's what it's called) where the trade ships are shut down and trade posts are converted to increasing resource extraction. I set all trade posts to auto-use the ability and sure enough all my trade ships stopped. After turning off auto-use and setting my trade posts back to trade mode, none of my trade ships would move again! I had to scuttle all of them before new ones would start running again. Please tell me this is not the way it is supposed to work.