Also having this issue - although I notice it only crashes when I click on the master bus in my 4th instance - which hosts all my synths and retro samples. Namely: Serum, Sylenth1, Massive, Plogue Sforzando, and Korg Triton. The other 3 are running just fine, they only have Kontakt, VI Player, and Synchron Player.

Threadripper 3970X / 256 GB RAM / Komplete Kontrol S88 / Windows 10 Build 19044.1645 / VEP v1.1298 iLok / Nuendo 11.0.41