mid-game de-syncs & black screen glitch with client app

[Highwayman]

I've got a couple of issues having returned to the game after a long hiatus.

1. the Downlord client beta 0.93 constantly attempts to steal priority over the game, and goes to a black screen, seems to go away if I disable Gysnc and run windowed though. Any fixes?

2. the more important issue... De-sync mid-game, this is not happening early on in the game as have played some games to 5 hours before it's happened, more often an hour or so is typical in a co-op two humans vs two AI match with minimal mods enabled usually 20k map size. unit cap of 1000 etc, Any ideas?? I've no such problems with other games but read something about a ICE adaptor? is that in the current client yet?


Spec of both machines are pretty overkill for the game, mine being the higher:
i7 9700k Octacore @4.6ghz, 32gb DDR4, Gtx1080ti, Windows 10 pro latest build, no 3rd party Antivirus etc, just good old Windows built in stuff. Firewalls open, my D7000 Nighthawk router is also fully opened. Any suggestions? both our internet connections are above 50mb/s down and 12mb/s up.