I have a licensed version of KVM Pro, v3.5.7 Build 00103
I installed Win10 on a new desktop today, and added Multiplicity as a secondary machine.
For a few tries, mouse did work in KVM mode, but after a needed reboot, the mouse no longer works in KVM mode.
It does still work in Seamless mode, but that's not my preferred access method.
Firewall is off on both machines at the moment, primary and secondary
I've run the MPPortFix script.
I can connect to other machines in my network using KVM mode.