DW does not have colony ships on the build order screen. This may help you:
Colony ships are unique on a number of points. One of them is: They are, I believe, the only ships which are not built at spaceports and shipyards, but rather produced by the colony itself (whatever that means), or whatever it is that builds spaceports and shipyards at colonies. "Normally" (whatever that means), the game expects you to select a potential colony, click "send colonizer ship to this planet", and then the colony ship is built "automatically" by a colony and sent to that planet to colonize.
If you must build them manually, you must enter the colony management screen (f2 I think, it's been a while since I played), select the tab for construction queue, and then select colony ship to add it to the queue. I believe you will not be able to do this if you do not have a certain minimum amount of population, but I forget what that amount is.
Hope that helps.