Hyperion Esc won't exit MAME

[epetti]

I've had my Hyperspin setup working for a couple years now, but somehow my settings got messed up. The key controls in Hyperspin got reset. I got them mostly working again, but am hitting a problem that I remember I had way back when I first set up but can't remember how I fixed.
 
I have Esc set to exit Hyperspin, and it's also the key to Exit MAME. MAME is launched through HyperLaunch (an older version). Esc works fine for exiting Hyperspin, but when I enter MAME, the Esc key is not recognized at all. It's like some other program (Hyperlaunch, Hyperspin or something else?) is capturing it before MAME can see it at all. If I go into the menus and try to set Esc to even the UI Cancel option I press Escape either on my buttons or on the keyboard itself, and it's as if it was never pressed.
 
I'm using CPWizard as well. Don't know if that could have anything to do with the mix, but for full disclosure of what all is running...
 
Any idea what's going on or how I can fix it?
 
Thanks.