Dan flipped Venus so it's south pole faces north, which gives it it's clockwise rotation.
Since the models have axial tilt (try putting Earth out and see the 23.5 tilt), Uranus is at it's proper tilt.
This explains a lot, thank you Fiahowl.
I also just found out that for us that we can not flip around planets, there is an option to change the direction of the rotation under Dynamic Properties. Go to rot x which in earth is about 24 hours and put a minus sign in front of it. Negative time will not drag you into the past in Ubox, but it will make your planet keep its rotational period while at the same time the rotation will be opposite to what it was.
You probably now wonder what happens to the planet's moons and how are those affected. Unfortunately they keep going as if nothing happened.
I will make a clear report on this on the suggestion box. I will not report anything once Ubox is mainly a gravity simulator and a change in the rotation would affect the moon(s) in ways unrelated to gravity, silly me.
EDIT: Or you can throw a meteor big enough and fast enough to change your planet's rotation. Just make sure you are on bounce mode. Then delete the meteor and you are good to go.