1. Prone/Knocked down. If a figure is forced to go prone from an attack (ie gets a move to cover result from shooting but already in cover), or chooses to go prone what melee modifier does this cause for later actions against the prone model? Same as knocked down? Is a prone model able to be knocked down or do further results cause them to be wounded?
Prone is a completely different state than knocked down. I describe "prone" as a bullet whizzing by your ear, and you involuntarily duck back, crouching behind a tree. "Knocked down" is you were hit by the bullet and are hurt. If you get back up before you are beaten again, then you shook off the wound. If you get hit again before getting up and are beaten (and wounded and out of action), then obviously it was more serious. Think of it as an abstraction.
So, to answer your question, yes, prone is bad in the sense your opponent in melee gets a +1 vs. you, but not so bad that if you are beaten you are wounded and out of action.
2. Hidden deployment. Do the markers have to be placed within 1 long of your baseline, or is anywhere on the board okay? Are they static until you reveal the hidden group or they are discovered?
Those were suggestions, actually. I usually don't use hidden deployment in my games. That is more of a scenario-specific thing. In fact, we normally do scenarios where the deployment is dictated by the tactical situation. I can send you an example of one of our scenarios so you know what I'm talking about -- if you like.

3. Why is the Last of the Mohicans character Magua costed at 82 points when the identical Indian Warleader is 92 points?
Now, THAT I will have to check into it...! I will do the math and get back with you. I delegated that part to one of my coauthors and trusted him...ha, ha!

Feel free to follow up with more questions or queries if I did not specifically answer what you were asking. And I'll check into Magua. There WAS a second edition that corrected a mistake in the first edition on the "formula" for figuring out a character's points. I teach History -- not Math...haha!
Mike Demana
www.firstcommandwargames.comhttp://leadlegionaries.blogspot.com/