What macOS versions does the driver you are installing claim to support?
Does the M-Audio device show up in Audio/MIDI settings audio devices?
Avid info for old M-Audio drivers is supposed to be here:
https://avid.secure.force.com/pkb/ar...t-Track-Family
But that's all screwed up and the link for the Fast Track Ultra is missing.
Avid dumped M-Audio, it was a business failure and support disaster for them. It's now a seperate company making low end stuff. I don't think the new company took over the Ultra product line so they are not responsible for updates.
Maybe somebody from Avid can at least fix the broken link issue.
The best advice you are going to get is to throw that interface out and buy something from a vendor who provides good product support. Focusrite being the canonical low end interface vendor many of us recommend (Focusrite also make lots of higher end interfaces) but you are going to need to make sure any interface you buy now has drivers that are supported on Mountain Lion. There are no end of nice interfaces spanning a large feature/price range, from vendors such as UAD, RME, Focusrite, Presonus, Apogee, Motu, ... and a bunch of other vendors I'd not touch with a ten foot pole.