I had a similar experience, briefly maintaining an OpenX install until one day we had a security issue. Turns out that nobody had been applying software updates and that software has lots of problems with it. I spent a week getting it up-to-date to be sure I had everything cleaned out from the hack.

At the end of the week I decided that the client wasn't allowed to run OpenX anymore and we found a different solution that worked within their CMS. Less bells and whistles, less problems.