A few parts to this topic, loosely related:
1. Are units with stands supporting a combat (but none actually contacting the enemy) eligible to be shot at? They would be in WM, but I'm thinking that the explicit inclusion of those units in the engagement in WMA would make them ineligable?
2. If a regular unit charges multiple Skirmishing units, do the Skirmishers Evade the charge individually or as a whole? For instance, if a unit of Cavalry inside 10cm charges a unit of Light Cav (Skirmishers), and makes corner-to-corner contact with a second unit of Light Cav, does a) each unit stand and shoot and Evade if possible in sequence, b) the units each have to score a hit for either to evade, or c) the units have to score one hit between them for either to evade.
3. Does anyone have enough experience playing with or against Huns or other Skirmishing Cav armies to have suggestions for dealing with them? I played a solo game tonight of Huns v. Romans, and Huns seem like they'd be a very frustrating opponent. It seems like the quantity of shooting they put out is large enough to disassemble just about any organized defence, and frankly catching them in order to take the offensive is difficult. Of course once you do get a successful charge against them, the charged unit is likely to be wiped out.
The only ways I can see to counter them would be to hit them repeatedly from close range with Cav and hope they fail to hit with their stand and shoot, or to have multiple potential chargers so they would need to evade beyond missile range or face a second charge with no option to evade, thus forcing them to at least make a command roll to get back into missile range.