Since Steam launch, every week has been Gray Elf with repeating classes in rotation
Steam ADOM Deluxe, release version:
In Weekly Challenges, every week since launch we have been given Gray Elves only with no exceptions, and classes has been the same ones in rotation. I assume this is meant to be random but I think by now we can safely say that it isn't.
Issue has been reported on ADOM @ Steam forum and in the official ADOM Steam Discussions previously, where Ravenmore responded on May 4th that it would be looked into.
The pseudorandom generator we used to calculate the challenge game settings wasn't very good. We now use an improved one to generate more random values.