I've been working on this solidly since my last post.
Curently, I have two files:
BackupMenuLauncher.item, which is in /etc/bootloader.d/ and runs when you start up your N900 with the keyboard open.
This file makes a ramdisk(and now, a tmpfs), loads all required files into it, and copies the second file, the actual program, from /opt/BackupMenu.item, then chroots into the ramdisk launching that file.
Code for each of these is pastebinned in the above links.

When I run this from the Maemo terminal as root, it works(as best I can see of it). I get errors on not being able to use udev(as its already running), but it actually seems to launch the script fine.

When I run it from the bootmenu-console, everything works fine until the launcher chroots, at which point it apparently dies and drops back to the bootmenu official menu.

Any ideas on what I'm doing wrong?

P.S. How do I get /etc/mtab in my chroot? "mount" does this.


edit: Yea, still having the problem.

edit2:
Found it. The second file was in /opt/, which is its own partition... which isn't mounted deliberately. :\
Moved it to the root partition, worked great.

edit3:
Sooo... working away at it. I'm having trouble mounting the SD partition; getting "invalid argument". I'm sure its something simple(or maby not...)

Thanks,

-Rob