Not possible to add 2 "secondary PCs" adding a second removes the first,

I have used multiplicityy for years through many versions. This failure began after an update to Win 10  1803  64 bit.  two are Pro, one is home.  I tried many setups, some with the "Pro" being primary some with "Home" being Primary.

Every setup ended with this failure:

Multiplicity 3.44 Can add only one "secondary"PC adding a second "secondary" knocks off the first one.

I tried fully uninstalling then re-installing multiplicty on all PC's

I then removing "homegroup"

I next tried every variation of "sharing and access" I could think of

I nextre-setup the 3 PC's on a new "workgroup" which I named "FELIX".  They do all appear under "network" and are manually accessible

The same fail remains "Multiplicity 3.44 Can add only one "secondary"PC adding a second "secondary" knocks off the first one."

I next looked at the MS Firewall settings.  Stardocks manual says to set the network as "Private" but the auto setup by Win 10 was "Private/Domain", so I manually edited the firewall settings to be only "private".  This too continued the same "Fail".

All three PC's work properly as primary or as secondary.  But adding any of them as a second secondary" knocks off the first one.!

I must be overlooking something?  Please help   carym@afriend.com