Space Arena 2.7 does not have the option of selecting multiple add-on ships. You can
however, alter one of the graphics files in the PICT resource and change the UFO.
  Before you get annoyed, this is a very long game. The senerio stretches on for ages.
It ends when you have killed the aliens a certain amount more than they have killed you.

  Along the way, you will encounter things like wormholes, asteroids, midspace
battles... You can even travel back to Earth.

  There are no secrets to the game. Just so you don't spend your time looking for them.
If you want to complete the game, you'll have to do it on your own.

    If you are not registered, you MIGHT get to see at least one communication senerio,
but that's about it. There are approximately 10 different communications, and you
only see the first one, and maybe the second if your fast.

  If you are registered, you can complete the game, if you can...

   By the way, you can play as long as you like, there is no death or anything.

  If you do edit it...fine...go upload it or something...