[Suicide Junkie]

Sounds like you found the downloads, and are almost there.

As stated below, you need the Full install, rather than the patch.
For the planetpack, as it sounds like you want, you should dump the entire contents of the planetpack into your c:\MM\se4\pictures\planets\ folder.
This will overwrite your planets.bmp, and add almost a thousand portraits.

It works similarily for components, facilities and combat.