laithis - I have a short attention span, but maybe this is the answer to your question
Here is how I did it:
1. Unzip Maxx's zzzzzSuperMegaManilapackVers19 - I just extracted all the files to a folder of the same name.
2. Place the unzipped folder into C:\Program Files\PPCkitchen.org\BuildOS\USER_OEM
3. Open BuildOS, and there should now be an OEM category, and it is called SuperMegaManilaPack19
You shouldn't have to mess with the PPCKitchen_OEM or do any repacking of anything at all, just drop the unzipped folder in to USER_OEM.