RayB,
I use GameLauncher as well. What I did was to grab a copy of the catver.ini file from
www.catver.com. GameLauncher limits the number of categories, so I modified the catver file to output only about 10 different categories. Once that was done to my liking, I ran Tri ROMS Auto, which you can also get from the Downloads page of the catver site. This broke the roms out into multiple sub-folders based on the 10 categories in my modified catver file. From there, it's really easy to set up multiple config files in GameLauncher for each category, each referencing a different folder for the ROM list.
I'm sure there's an easier way to do this, but I'm pretty much a noob at this myself, and this method seemed easiest to me.