After updating Fasteroids to include coloured UFOs the old blue UFO should have disappeared. I thought a particular command initialized from 0 to number -1, but in fact it initialized to 0 to number, thus I wasn't testing for all instances of the object.

All types of UFOs theoretically have the same chance to appear, however it seems to me that Red/faster UFOs appear more frequently. This is probably due to the fact they blast across the screen a lot quicker than other UFOs.

With fasteroids-5c0f83d.zip you really shouldn't see the blue UFO anymore!