This has happened to me as well. Tried the upgrade to Version 4. This hung or crashed when trying to add secondary computers (3 installs). Rolled back to version V3.57 (direct install), then V3.6 (installed via ObjectDesktop). Both found the 2 other computers and connected without issue, but when adding to the grid, only one is accepted. Adding a second kicks out the first.
Disappointed. V3.57 was working fine previoiusly.
Phoenix
For your 3.60 installs (Latest in 3 is not 3.57), you activated with eMail address and password. That defaulted to the Object Desktop version on your account, KM, which only has 1 Seamless Secondary.
Go to your account page
https://store.stardock.com/myaccount/products
to get your KVM key. Go to the About tab in MP3 to change the license on the Primary.
Sean Drohan
Stardock Product Lifecycle Manager