Here is a discussion on creating a monster scenario using all present options and workarounds.
http://forum.shrapnelgames.com/showthread.php?t=39304
Here is a thread on the things that are broken about scenarios
http://forum.shrapnelgames.com/showthread.php?t=43209
Yes, mentioning scenario in the forum name was a bit of a hopeful on my part. But then later we found out that many of the things which were supposed to be part of scenario are broken so we never did really end up with much.