Quote Originally Posted by OmegaFenix View Post
For the main story mode you need to finish it before you can change batsuits. For challenge maps you just select before you enter the challenge selection screen.

Also its not a "cheat code" its a DLC code or Unlock Code. "Cheat Codes" dies back in the 90s
I finished the game a couple of days ago. At the challenge maps I can select a different outfit for Catwoman but nothing for Batman.

When I finished the game I did get a message that said that different suites are unlocked but so far I haven't had any luck finding them. Game is up to date in steam so I really don't know what it could be.