You can activate the cheat mode by holding down [Shift], then
[Enter] or left mouse button. The cheat mode allows you to see the
whole world, change anything in all the cities in the world and do
all the other stuff mentioned in the next text.
When you're on the "choose your civ" screen, press esc and type in
Hold down and press 123456789t.
Older versions, ALT-R will randomize enemy leaders.
If you look at the civs using the Shift-56 cheat and F7, civs can go
into "Vendetta" mode and be more inclined to go to war with you,
charge you more tribute, etc.
You can choose your own colours for your tribes if you use debug.
Get into the directory and type for example --debug civil0.sve.
When you get the prompt from the debug routine, type d for display.
The computer will then print out the first 80h bytes of the file.
I believe it is the third byte which is the human player. Use e
for edit and by changing the numbers you can get any colour
available 00=red (but then you act like the barbarians and there
are a couple of other twists) 01=white, 02=green, 03=blue,
04=yellow, 05=light blue, 06=pink and 07=grey.
The way it works is that, when you tell a settler unit to do
something (build a road, mines or irrigation, for example), and you
have at least one other unit that still hasn't been moved
(blinking), you can go back to the settler unit, click on it to
start it blinking again (click on its icon in the box that comes up
when you click on the unit), and then press R, M, or I to start the
settler working again. Then you go back and click on the settler
again and hit R, M or I while it's blinking, and you keep doing that
until the improvement is built (you can tell it's done when, when
you click the unit, the icon in the box no longer has a letter on
top of it). This works best when you have the "end of turn" feature
on, and of course you shouldn't move other units until you're done
with the settler. If you do this right, you can get your settlers
to build anything you want in just one turn (normaly it takes 2
to 12 turns)!!