Yeah, sorry about the confusion Ginsuvictim, it is left/up, left/down, left/left, left/right and right/up, right/down, right/left, and right/right. The games I tested it on were X-men and TMNT.
I bought the panel from a guy and he didn't give me any info on it. I just plugged it into my pc and hoped for the best. It does work, but the configuration was all screwed up so I manually went into mame and set each direction and button. I tried doing what you had mentioned as far as combining the two, ie left=r, up=t therefore left/up=r+t, but it didn't work. The character on screen simply wouldn't respond, so I each direction got its own keyboard button. I figured there has to be a better way to do this, but I am a newb at this and couldn't figure out much on the web from my search, so I thought I would post and get some help from this community.