Cheat codes:

To enter the in-game cheat mode at any time, type any code as you play (it 
won’t work if the game is paused). Then hit Enter. If it doesn’t seem to work, 
try them again. Type them carefully when you have colonists selected: Pressing 
certain letters can cause a selected colonist to initiate a behavior trait (for 
example, pressing F gives the Flee command).

Heal your guys:
gsaheal - Heals all colonists (not terminated) back to full health.

Look into all rooms:
gsaroof - Removes all roofs (takes awhile) so you can see into rooms.

Kill the aliens:
gsaswap - Swaps sides (allows you to control aliens); use following the kill 
cheat to eliminate selected aliens.

gsakill - Kills selected characters (your own, or swaps, selects, and kills 
aliens).

gsastop - Stops both aliens and colonists from acting, causing them to just 
stand around; type it again to toggle it off.


More Weapons:
gsabog - Creates a BOG weapon at the cursor that when you pick it up gives you 
extra defense and lets you lock doors.

gsaknife - Creates a KNIFE weapon at the cursor that when you pick it up makes 
you invisible to aliens (they won't go for you when they would normally see 
you).

More guys:
gsacmdr - Creates a commander at the cursor.
gsamedi - Creates a medical officer at the cursor.
gsaboff - Creates a technician (boffin) at the cursor.

Win and move on:
gsawin - Wins the level no matter what (so you can continue to the next).