Unit percentage chance of appearing option?

[PoorOldSpike]

Is there a setting in the Editor to assign a percentage chance of a unit appearing in a scenario?
For example I want the AI force to be different each game, so if I assign an appearance chance of say 50% to each enemy unit I know about half of them will probably not be appearing, therefore each game will be refreshingly different.
Is it possible to do that?
(and before you ask, I've searched the editor manual 3 times without finding the info, is it a lightweight manual or is there a deeper more detailed manual somewhere?)..

[dalfrede]

I got this examining US Corp Gela scenario

Place unit
Select unit – shift click

in Unit Parameter window
click Edit Trigger
in Unit trigger window
click Random Condition
Add random condition

I suspect that only way to learn these things is spend a long time clicking on all the buttons to see what is there.
Or examine Nico's scenarios and learn from him.

[PoorOldSpike]

I got this examining US Corp Gela scenario

Place unit
Select unit – shift click

in Unit Parameter window
click Edit Trigger
in Unit trigger window
click Random Condition
Add random condition

I suspect that only way to learn these things is spend a long time clicking on all the buttons to see what is there.
Or examine Nico's scenarios and learn from him.

Thanks, that seems to work!
PS- I've been spending lots of time in the Editor trying tests and stuff like Indiana Jones in search of holy grails..