there are some open source programs and ports of windows based ones, but its much easier to run windows to do it because a lot of the apps are written with the .NET framework dependency. you could run WinE, but it doesnt like dannykay's cso compressor.

as far as the .deb/.tar.gz, you will need to use the tar.gz's. knoppix is the shi-ite when it comes to these kinds of things. im not a guru or anything, but i have been f*cking around with knoppix forever. knoppix 5 runs fine on the EVOn400c (i have one), but you might wanna go with Debian. knoppix is a little hard to install on the n400c because its soooo big. also, if you upgraded the ram, youre better off than I. i dual boot windows and debian on my evo using the LiLo (linux loader). i would recommend this set up for psp hacking.

and, youre welcome for the XMB submenu customization. the code and theory were developed by myself and iguanahak, though ill never get credit for it.

peace, bro, and good luck.