Hey George, I am in the same boat as you. I too am going to go to the ATEM protuct and have found the BMD people not very helpful. They did point me here though. I know a couple of ways internet streaming can be accomplished. 1 - teradek cube -
http://cube.teradek.com/cube_family.html 2- You could use a computer, mac or PC, running an encoding software like wirecast, or windows encoder. 3- This would be a very reliable solution
http://www.viewcast.com/products/niagara-systems
As for CG, Media Clips player, and such... Well that is my problem as well. I too am looking to use a mac for this even though everything we have in our studio is PC based. I have found 1 possible media clips player made by Softron -
http://www.softron.tv/products/ontheairvideoexpress.html If i go to the mac world, this looks like it would work GREAT and solve alot of problems. As for CG, i am looking at using Adobe products and loading them into the ATEM via network cable. Download the ATEM manual from the Blackmagic web site and read it. I did and I learned so much more than reading the sales pitch stuff. Also, check out videos on Blackmagic ATEM on you tube. Very informative. There is a guy on this forum named Bob Zelin who seems to be real knowledable about BMD products. He has a few videos you could watch on you tube. I am hoping to get some more answers like you.
Hope this helps....