I'm seeing an issue in the Windows 11 preview with Multiplicity KVM mode. Everything loads and works great until you select "Switch to another monitor". At that point Multiplicity "disappears" from the primary computer. It is still running but the window is not visible. It appears it remains on the original monitor as you can no longer click on anything on that Primary monitors screen (this is a 3 screen setup with Multiplicity KVM on the middle monitor).
If you use the taskbar or Task Manager to stop Multiplicity, you can restart it but only video is working. Keyboard/Mouse controls do not work on secondary computer.
EDIT: Should have mentioned, Primary is Windows 11 Pro Preview, Secondary is Windows 10 Pro 20H2.
I'm having the exact same issue. Occasionally, as in once in a blue moon the switch monitor button works. But usually Multiplicity just "disappears" as described. Often times you can get the screen back by right clicking the task bar and selecting the named window, but the keyboard and mouse will not work on the remote PC. The only solution to this is to restart the Multiplicity processes. I've also noticed if you try to reload a connection you get one or more blank connections (see image below) which also appear in task manager.
My primary PC is running Windows 11 Pro 24H2 Build 26120.1542 Windows Insider Program Release Preview and has three monitors. The secondary PC is running Windows 10 Enterprise 22H2 Build 19045.4780 with two monitors (one virtual).
