Well, skining/branding ZD is one thing and having that available in the install package is another.
In my previous post I was talking about the branding part; and I suppose you could look in the Prism config files to change the "zimbra" name on it. I'm not sure if that will do it, but it's the first place I'd look.
About the pre-packaged skin/branding. I'd suggest you look at:
Bug 38351 – Ability to Create Custom Installation and, maybe,
Bug 44711 – Allow downloading of skins from server.
NOTE: I haven't checked, and I don't know if that would violate the
branding guidelines, I'm just offering options