Just use the scripts to change them.
Use Terminal, type "su" (without the quotes, type "scripts", type "name of livewallpaper" done.
i can't get my wallpaper to change. after i ran titanium backup its now stuck on my old wallpaper that i had before i changed over to jrummys rom. i only can change it to the stock live wallpapers and when i try to change it using terminal emulator i get this "goodies folder not found on the root of your sd card"
You need to install the goodies.zip. Install it like you would a ROM. Mirror: Froyo_Googies_update.zip
+1 You have to have the goodies installed in order to use them, I guess I should have mentioned that before but thought it was implied.