You are allowed to re-skin and re-model any model from FPSC default pack but you can ONLY use it on FPSC. You aren't allowed to use models or skins from FPSC default pack outside FPSC.
By re-modeling i meant adding custom made models to the default ones, one exemple is adding modeled arms to the default weapons on the FPSC package.
About the model packs, im' pretty shure it's the same, but only the official model packs, the custom made, you must ask the owner.
My love is seperated in 2 parts, 1 of them is 3ds Max 7, the other; FPSC.