easy steps by me.
1.) back up your flash0
2.) overwrite the themes that you have to appopriate folder in the flash0
3.) be sure that "vsh" folder is very important to your flash0.
4.) enjoy!
Q&A
Q: how can i go to flash0?
A: turn off completely your psp. while opening, hold R.
Q: where is the flash0 menu?
A: when "recovery menu appear" go to "advance"
Q: where should i put the themes?
A: for icons only, open the "vsh" folder then open the "resource" folder
overwrite the "topmenu.rco" file. exit to recovery menu.
for fonts only, look for "font" folder (also in recovery menu)
overwrite only "ltn0.pgf" file.
for gameboot only (the scene that appear when you open a game)
overwrite the "gameboot.pmf" file in resource folder.
