Cityscape cheat mode (beta version):
Hold [Al
and type ufo cheat at the main interface. The message bar will confirm that cheat mode has been enabled. Enter one of the following codes to activate the corresponding cheat function.

Effect - Code
Cancel cheat mode - [Al
+ [Esc]
One more of all equipment - [Al
+ [Keypad Plus]
Flip dimension - [Al
+ 0, 1, 2, 3, 4, 5, 6, 7
Toggle auto-save - [Al
+ A
Force Base mission - [Al
+ B
Force UFOs to crash - [Al
+ C
Toggle dimension map - [Al
+ D
Toggle build base facilities - [Al
+ F
Test alien dimension - [Al
+ G
$100,000 - [Al
+ M
Show number of aliens in buildings - [Al
+ N
Toggle instant project finish - [Al
+ P
Toggle allow all manufacture - [Al
+ Q
Toggle allow all research - [Al
+ R
Force Overspawn - [Al
+ S
Force apocalypse (terror) mission - [Al
+ T
Toggle view all UFOpaedia - [Al
+ V
One of each vehicle - [Al
+ X
Show people tube connections - [Al
+ Z

Tactical cheat mode (beta version):
Hold [Al
and type tac cheat. The message bar will confirm that cheat mode has been enabled. Enter one of the following codes to activate the corresponding cheat function.

Effect - Code
Cancel cheat mode - [Al
+ [Esc]
Toggle training - [Al
+ T
Toggle hidden terrain - [Al
+ H
Toggle hidden units - [Al
+ V
Kill hostile units - [Al
+ K
Toggle invincibility - [Al
+ I
Toggle weightlessness - [Al
+ W
Increase music intensity - [Al
+ F
Decrease music intensity - [Al
+ G
View FMV sequences - [Al
+ U