I agree. We have also being accesing computers in our office through remote desktop since march the 12th.
May be better to just use a remote desktop aplication combined with another one for the comunication, even using your phone hands free while watching the screen, if you need both to be watching the same screen? In the remote desktop you can usually select to show your cursor to the other guy, so you could point things, etc.
In any case, only one computer has to have Archicad installed and its license. The other one is just "seeing" and controlling the other pc through the net.
ARCHICAD 26 SPA