The 6-in-1 Snitz Common Expansion Pack contains these popular mods: 1) Site Integration 2) Header Cell 3) Proeder's File Attachment 4) Email All Users 5) Private Messages 6) Gatekeeper.
The only changes you will have to make are to the config.asp file in each folder so that it matches your own - there are no other code changes to make.
Each mod is in it's own folder and the installation steps are methodical. Study the readme files before beginning and it should be easy to understand and implement.

Correction: *removed admin_compactdbs file from the Gatekeeper mod - the mod does not belong.

Please be sure to return here to rate this mod after you have it installed.