strap loader is where it normally shows the wiimote and condom and strap. if thats the kind of file you have, it should be as follows
X:\private\wii\app\RSBE\pf\menu\strap\StrapEn.pac
but if you have the actual main menu then like this
there's some different files, but mu_menumain.pac, the main menu, goes in the folder "pfmenu2" in the "RSBE" folder
please post a link of the file you downloaded to clarify what the heck you have.