With 1, pick one person in front to do more initial damage, so the mob is always in front of the main char, so your alts will be in back and can cast.

Or as you have seen, just use IWT and your alts will face and try to melee. It doesn't hurt any, you can just cast while they are meleeing.

Now if the mob keeps moving and you are keep having to make them face different ways, then add your tank to the group and park your alts. You can pass a movement key to your alts and they will break follow, then run up to the mobs on your tank and your alts should be standing back so they can cast.

For 3, can your laptop get to the web? If so, then look for its IP address (open DOS command window and type in /ipconfig). Then you can use that to setup your key broadcasting software so it knows who to talk to. To make sure the PC and the laptop can talk to each other, try pinging the laptop. From a DOS window type "ping" and the IP address from before. "Ping 192.168.0.2" You will have to put in your the laptops IP address.

Hope that helps and good luck.