I failed the madness-level a couple of times because I was only using basic miners trying to preserve units. It got much easier when I used upgraded miners and got to 2000, then 4000, then 6000 units mined per minute.
If you want the Thels to go after the UIOs, help them with a few missile launchers to clean up in front of the UIOs. Repair stations as a front wall work wonderfully to distract the UIOs, btw.
 "The Space Game"){kind=icon}
 "The Space Game: Missions"){kind=icon}