Edit the "Max2.ini" file and use the following settings:
This should give you access to all campaigns.
Again, here are cheats that work only with the standalone,
single player missions:
[MAXSPY] This is toggle. Turn it on to see all the units on the map,
even the ones outside of your normal Scan range. You still
cannot target units that are outside the Scan range of one
of your units.
[MAXSURVEY] This is also a toggle. Turn it on to see the locations
of all the material and gold resources.
[MAXSTORAGE] This will fill all of your units and buildings with the
maximum amount of material.
[MAXSUPER] Select a unit and use this cheat code. That unit will be
upgraded to the highest possible level.