Just a quick update on my previous post:
Having experienced graphical glitches / artifacts this morning in addition to the freezing / high CPU usage, I decided to completely remove the Displaylink software & drivers, and completely power down both laptop & dock for a few minutes.
Having already manually removed the Displaylink folders & registry entries, I reinstalled the latest Beta 4, and I've been totally glitch-free for nearly 2 hours and counting - which is a new record!
Fingers crossed
Windows 10 Insider Preview | Version 1607 | Build 14376.0