Well, to tell the truth, that was the original plan, but GPS navigation packages for Linux are few and far between, from what I've noticed. So far I've only come across topo maps and basic street maps... if that's all I wanted I could just print out directions from Mapquest before I go anywhere.
As for the GPS mouse, I haven't gotten the chance to test it yet... I switched over to GentooX Pro for speed's sake, I wanted to compile something lightweight that'd only do what I need it to... after a few days compiling, I ended up breaking the hell out of my install... like I said, I'm a linux noob.
The installshield issue I attempted to tackle by normal means, but could never get it to do a direct install on my box... so I ended up installing it on my PC, putting the maps and the installed software into a single directory on the box, and attempted to bring it up. Luckily, it's a simple enough program that it worked that way, nicely.
Now I've just got to get Gentoo back up and running again.