I’m the author of Gate One. Let me know if I can be of assistance in getting it integrated into Zeroshell. Don’t worry about conflicts with the GPLv2 and the AGPLv3. I can write something up giving Zeroshell permission to use Gate One in the distribution.
FYI: The point of the AGPLv3 license in Gate One is to prevent commercial enterprises from copying the code and integrating it into their products without keeping it open source (or paying =). It isn’t meant to be a restriction on its use within other open source projects.
Note (already thinking about this): For embedded devices you’ll want to pre-configure Gate One’s server.conf with a few changes from the defaults so it doesn’t gobble up all the disk space with session recordings.