Flags and Artillary

[Forst22]

Slowly getting to grips with the latest version of the rules but would like clarification on the following

A) Dervish flags - can you have more than one?
B) Artillery - p54 says artillery can fire into scenery within 12" is this only at targets touching the edge as per the visibility rules? Or can they target deployed units further in?

How do you capture the flag?
If artillery is more than 12" away can it still fire at units in the edge of scenery ?

Thanks