how many games are showing in your "all games" list? should be like 9400-9600 or something.
I have found a couple of missing roms in that list for whatever reason (usually in the X's W's and V's), but I know for a fact Rampage WT isn't one of them (I have it on my list).
This is what I did to account for the missing roms, I don't know if it will for for your setup. I made my own gameslist comprised of just the Roms that I have in my Roms folder called "My Games," by using the Gameslist feature. You can also get there from the configurations menu selecting the gameslist tab and launching the games list editor from that tab.
Anyways what I would do if a game that was in my rom folder wasn't in the "All Games" list I would transfer over any rom from "All Games" to "My Games" that I knew I didn't have, something retarded or easily idenifyable like Mahjong.
Then once it was in "My Games" I would right click on the rom and select edit. I would change the name field to the name of the game that I REALLY wanted in my list and then changed the Rompath to the name of the ROM in my ROM folder.
This has worked for me so far.