In halo 3, do i need online pharmacy without prescription to start from the beginning of the level to get the skulls?

Alright, I recently bought Halo 3: ODST, and with it, came the Mythic Disc. I have already downloaded all content but the Mythic Map Pack 2, but I have just been wondering if you needed to delete cheap Ampicillin the map packs already downloaded, or it might mess up? Are there any errors if you have the maps downloaded and you play on the Mythic Disc? Thanks, Raven.