I did try earlier today, but no luck. The created "app" fails to find application.ini even though it's there. Running it from command line and telling it where that file is also fails (foxbox -app /path/to/application.ini). I think i figured out why it doesn't work though. UXP broke/removed/stubbed xulrunner years back for some reason. AFAIK this box "hack" requires xulrunner, but i could be wrong. I'll keep poking at it.
Cheers
Cheers