grif091, thanks for your help. I have everything working much more reliably now, but I am not sure what exactly fixed it. I added 3 filters to my fridge, router/cable modem/server/switch/nas/printer stack (which is electrically near the EZServe) and TV, added a “dryer” phase bridge in addition to existing RF ones, resync’ed all devices as you suggested and upgraded EZServe to latest beta, 02.00.43.
Interface in IE is reliably stable, provisioning of links is faster and also more reliable and scenes are created with valid links now. I will continue testing but I got a feeling that the issue might be caused by some powerline noise I did not have when I was playing with 1.60. Thanks for your support anyway!
Update: I somehow managed to hang the interface again with the new setup. And again – nothing obvious, unfortunately, I was testing new action interface and was adding actions/conditions and testing them on a few switches. I had one IE tab where I edited actions and a second IE tab with details of some device with no activity from me, just the usual auto-refresh. I also had a TCP session open to port 8002, using netcat (read-only, I was looking at “ClusterResponse”s in traffic). At some point interface just became unresponsive, “Reset” on TCP interface worked though.