Has anyone tried this? I can add the GamBAS3 dependencies, and yumi_0.0.1-1_all.deb (the Debian version, not the 'buntu), and a new entry shows up under the System menu category. But (for me) it doesn't seem to do anything - not even look for a USB flash stick. (Oh ByTheWay, I'm strictly a Linux 'newbie'.)
(update Feb 16)
I did get the 'buntu version partly working on a live distro - it unpacks ISOs and adds entries to syslinux.cfg okay, but didn't initially make a /yumi folder, apply syslinux, and copy files like syslinux.cfg and vesamenu.c32 before adding the first ISO. Of course, it's only in the pre-alpha development stage, and there may be a "dependency-hell" syslinux-versions challenge in store.