Start the game with the "-TestMode" command line parameter. Start the game and 
click on the new "Test Only" button. Any mission may now be selected. While 
playing a game, bring up the tactical display and enter one of the following 
codes to activate the corresponding cheat function:

Result - Cheat Code
God mode - [Shift] + G 
Damage targeted subsystem by 25% - [Shift] + K 
Repair targeted ship - [Shift] + R 
10 Quantum Torpedoes (only if ship can use them) - [Shift] + Q