I'll try to edit this posting over time and add some pictures, but just for now:
It is not supported to rip off, disable or uninstall aka "not use" TMG on an EBS security server.
In other words:
You must have TMG on duty on the EBS security server!
I really think that TMG is a really good product, but I also see people wanting for some reasons (internal, organisational, political) to want to continue using their existing Firewallproducts.