Bzipping isn't necessary, as they're very small files. Just add them to your downloads (I don't know what mods you are using, typical download helper would be under sm). They're not 100% needed, it's just a nice touch to have when making a professional map.
@Harry. Having to reply here due to the thread being locked. The reason they're so big is because they're made for 50 slot jb servers. I originally started bunker for the server I was teching, but eventually thought that they didn't deserve it (personalised banners etc), so just released it publically instead. Glad to see you like my maps, and thanks for the support.