Let us assume you want your users to be able to make their own bootable USB flash memory pens. You want them to use RMPrepUSB and also to use your OS payloads (of which there may be several), they also need to perhaps run Install grub4dos after formatting. Furthermore you want distribute a package that will install itself and create a Desktop and Start Menu shortcut.
A minimum configuration of files for v2.1.615 and later would be:
grldr (if installing grub4dos)
grubinst.exe (if installing grub4dos)
LANG folder - English.ini (and any other ini/pdf files you want)
Mke2fs.exe (if creating an ext2 volume)
PEtoUSB folder (if using BartPE option)
RMPARTUSB.exe.manifest (if using under Vista/Win7)
RMPREPUSB.exe.manifest (if using under Vista/Win7)
rmprepusbxp.cmd (if using BartPE option)
syslinux.exe (if installing syslinux)
touchdrv.exe (if installing grub4dos)
RMPrepUSB.ini (with your preset configuration menus)
YOUR_SOURCE_FOLDERS - a subfolder containing your boot files which will be copied onto the USB drive by RMPrepUSB.
You should now have a internally-distributable package for making your own 'brand' of USB drive.