I am calling my custom RDP program CODTSC and using RDX as the file association.
Initial development is complete and I have finished my personal testing. I put together a deployment package for my coworkers. We set up a sample RDX file with a special config tool that I also built for them.
At the end of the day we deployed it to a single user that uses RDP to connect to 5 different sessions. That user has RDP files provided for them. In the morning I will see how seamless the deployment went once the user gets a chance to use it.
Ideally this will work at least as good as mstsc and not introduce any new problems. The user does not know we made the switch. They will see it look a little different when connecting, but after that it should not change any thing for them.