I support the Character Animator team and keep an eye on the Forums. I have asked an engineer to take a look at your question and respond to both your questions.
> how can i input multi cam so i can move my two Character with two cameras and two persons acting for the scene
Ch can only track one face at a time, so for live production it can handle only one character. But with two computers, each running Ch, you could produce two characters live. You'd then need to use software like Telestream's Wirecast to screen-scrape the results and stream them to a third computer where you combine them, perhaps with another Wirecast? Not sure it can do that, but the folks at Telestream can tell you.
> is it's a funny show so some time the actor some time show his tongue can i add tongue exertions to mouth in Illustrator file ??
The simple way is just to add an extra mouth with the tongue out, and give it a key trigger (name the layer like "TongueOut (T!)"). Then press and hold the T when you want see the tongue.
If you want to keep the tongue hanging out while you talk, you'd need two sets of visemes (i.e. two Mouth groups), and then you'd trigger the entire tongue-mouth group with a key in the same way. This is more complicated though, as you have to apply an extra Lip Sync and Face behavior to the extra mouth group.
The next preview version (3) will allow you to just press the key trigger and not have to hold it down.