Hi, there is no direct upgrade path from ML5 to 6. Completely new.
No, the HomeSeer integration will not work today unless Blade wants to write the myServer 6 side of it.
There are not too many Homeseer systems in the mix anymore so less emphasis for integration.
Good to see you around still!
List what hardware you are using with Homeseer and possibly most are supported natively by myServer 6.
Than!