I'd highly recommend you to check out the original generals challenge maps and read trough the scripts. This way you can see how they did these scripts and you might get some new ideas.
To tell the map where the player starts, you need to make a script that spawns a CC and a dozer at a location with a direction. If you want to make this challenge accessible for all factions, you need to add each faction manually.
For example:
If: player'[human player]' is faction name AmericaLaserGeneral
Then: Spawn object 'Lazr_AmericaCommancCenter in Team 'team[human player]' At position
(333.33,333.33,9.00) rotated -135 degrees.
Spawn object 'Lazr_AmericaVehicleDozer in Team 'team[human player]' At position
(433.33,433.33,9.00) rotated -135 degrees.
Originally Posted by: Queryk