I've got a sub-sub-theme of Omega, namely, a subtheme of omega_kickstart_theme, which is in turn a subtheme of omega_kickstart, which is a subtheme of omega.
Here's my .info file (pastebin).
I've stuck the file freshstop-omega-alpha-default-narrow.css in the /css folder, and that's supposed to be all she wrote. It's supposed to load for the narrow layout.
But when I resize my browser and check for this file, it's not there, nor are its styles. Cache cleared, css aggregation off, etc. Firefox.
I've also tried freshstop_omega-alpha-default-narrow.css (note underscore instead of dash).
Hmm. Any deeper tips? Place to start debugging?