I'm running WahCade under FC15, and it's working nicely now that I have dumped Gnome3 in favor of Xfce.
Recommendation: Run wahcade-setup from a terminal window instead of from the pull-down menu. You can see the error messages when it craps out.
I had problems with mameinfo.xml and mame-0.ftr. I resolved the problems by changing the List Generation Method in Emulators/List_Generation from XML to "ROM Directory". Then I generated the mameinfo.xml file using the circular-arrow button on the MAME_Only page. Once that was done, I would get the mame-0.ftr error when I pressed the Setup Filters button on the MAME Only page. This was cleared by changing the List Generation Method back to XML, then running the Setup Filters function.
Took me a while to figure this out, but I've done it successfully on two different machines now.