For all those who are having trouble with it (also make you sure you have Cabal Online: The Revolution of Action selected, and not Cabal Online):

If you didn't set it to register the game manually,
1. go to Tools> Options> Games
2. click the not installed tab and scroll until you find Cabal Online: The Revolution of Action
3. click manual
4. click browse for the game path and detect path (find the .exe file in your Cabal Online(NA) folder for both
5. click apply and it should work.

If that don't work try restarting x-fire or your computer. It took mine awhile to figure it out, but It works fine.