I am slowly making way on building my cabinet, along with having got a test control panel created. Below is a few pics, I know its not much currently but I wanted to create a test panel of sorts before I go and create a good 'final' control panel of sorts.
So my problem is this: When hooking up the trackball to the Mini-Pac it works just fine on my laptop, my laptop picks the mini-pac up right away and in the lower right corner it comes up saying how it recognizes a new keyboard and then that it recognizes a trackball. It then allows me to use the Trackball just fine a mouse, or inside of mame when I enable it.
When I hook up the mini-pac to my desktop computer that I plan to be using in my cabinet everything but the trackball works. In device manager it appears that the trackball is showing up as a unknown USB device. I've tried researching this issue, and see that by having a ps2 mouse/keyboard plugged in can cause it to not work. Well, I tried unplugging both of these and rebooting and it still does not pick up the trackball.
So any ideas? The trackball works fine on my laptop but not on my desktop. Both are Windows XP, both as up2date as they can be. So any help as to why it may be doing this would be awesome! I am clueless as to what could be causing it, since I know windows should have built in driver support for this so I don't see why its not being recognized on my desktop.
**Edit** I got a question I'll add in. The Mini-Pac has two ps2 ports on it, why is this? I only need to use one of these to connect it to the computer I believe, correct? Is the other port to connect another mini-pac to if needed?
Now for a few images to show ya what I am working with currently:

