4
OK, this has been finally fixed.
I spent a lot of time looking in the wrong area. Somehow, the answer has been deleted, and when SmartFAQ doesn't find one, it creates a blank screen. I've added the answer from tcnet, and now it's working fine. I've check all answers, and all of them seem to be working now.
If you experience again any blank pages at XOOPS FAQ, please let us know and we'll fix it.