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.