I have to use the old GUI (Classic UI v7.x) because the new one doesn't works (RDM 8.1.0). I have refresh problems independently of which and how many sessions are open.
You can look at my old posts about this problem.
I have Windows XP Professional SP3 with a lot of .NET installed (from 1.1 to 3.5).
If i uninstall RDM and .NET 3.5 and reinstall them, for a short time (few hours) the new GUI works, than the problem reappears.
Do you think that these several .NET interfere with RDM ? Why the old GUI works well (very well) ?
We use a thirdparty for the UI and it's a more complex one. I will update the third party soon and I hope this will resolve your issues.