Here´s the BOR.elf (all the .PAK mods for Beats of Rage Ps2 here: dl.openhandhelds.org/cgi-bin/gp32.cgi?0,0,0,0,11). just put it inside a folder with the .pak file named BOR.PAK. there´s no menu to select different paks so if you want to play different bor.paks, you have to make multiple folders with the bor.elf and a bor.pak inside each one. then use uLaunch.elf to load the elf.
I didn´t really port ulaunch.elf. I don´t have the skills to port anything, lol I just switched the usb drivers with working ones for the ps3 and compiled the elf. As simple as that.