Alex,
>1) I want to use MSN Messenger programmatically for customer support, both through chat and especially by offering the option to give us limited control of their machine, similar to what you do with NetMeeting. All with minimal complication to customer, but naturally with good security.
The Remote Assistance feature already built in to Windows and MSN Messenger works fairly well. I've used it quite a bit to fix up stuff gone wrong with my daughter's computer which is 800 miles away from here.