I was using UltraEdit 3.3 on Fedora 17 with no problems. After the upgrade to Fedora 18 it continued to work fine. Then I noticed there was a newer build of 3.3 on the IDM website, so I downloaded and installed it. Unfortunately, it didn’t work. I guess it was a later build for Fedora 17, not a new Fedora 18 build.
I dropped the guys at IDM an email and they did a new build straight away and it worked fine. This build is available from the website now.
It’s nice when people write cool apps and back them up with good service when you need help!