After a bit more testing, I realized that RunOnSwitch seems to work fine for me with other command lines; it just doesn't like devcon.exe, or devcon.exe doesn't like it, for some reason. Maybe there's some weird timing issue. I'll try adding a pause before running devcon.exe and see if that helps.

--EDIT--

No, that didn't help. It's perfectly bizarre, because when devcon reports that the mouse is enabled, the mouse is actually disabled, and when it reports the mouse is disabled, the mouse works. Yet when I use devcon to enable/disable the mouse in a normal command window, it works as expected. For some bizarre reason, using devcon with RunOnSwitch causes its effect to be 180 degrees out of phase with what it reports. Any idea why this might be happening?

Two words: PowerPro, again. I know, it sounds like I'm a freakin' PR manager for it--which would be unusual, since it's freeware.

PowerPro can show a Start menu at the mouse position when you left-click, right-click, middle-click, whatever, on the desktop or anywhere else you choose. Another alternative is to show the Start menu when you simply "bump" the mouse against an edge of the screen.

I keep recommending this program because it really can do almost anything, in terms of interacting with the computer. But many people find it very complicated to set up, which is what keeps it from becoming a hit. If anyone is interested I can post a single-purpose PowerPro config file for the Start menu thing or any other thing, when I have spare time. Then someone can just overwrite the default config with the single-purpose one and instantly have the feature they want, with no effort. With a simple config, PowerPro only takes up a few hundred KB in memory.

I understand EAC (http://www.exactaudiocopy.de/) can rip a CD to a single WAV file that you can then encode with the program of your choice (including EAC), but I've never tried it myself. EAC is universally recognized as the best ripper in the world, and it's free, of course.