Cactus Game Design Message Boards

This Question could be simple due to the fact that i am getting back into the game but here it is. 
Pre rescue attempt
My opponate plays Simon the magicain and plays magic charms on him. 

My opponate makes a rescue attempt  with 7/6 charecter sa not important.  I block with Seven wicked Spirits and exchange it for Simon the magician.  Now that the exchange is complete does that mean i can use magic charms(or what happens to magic charms)?  Opponate said no and i went along.

Relevant SA
Seven Wicked spirits: you may inturpt all fortresses and exchange this evil charecter with any other evil charecter in play or set aside.

Magic Charms :Protect your magicians frm capture or conversion.  You may discard this card from your magicians durring battle to capture to human heroes. (may be activaited on magician).

Here is another question though. Can you exchange for the character with an artifact on it, and then deactivate it as your own art, putting it in your art pile? Or is the artifact still under the opponents control?

so, can a player deactivate a magic charms that is on his magician in an opponents territory then?