HL2 Holographic Emulation - Hands tracking not working

Unity 2019.4.3f1 (LTS)
MRTK 2.4.0 installed

Trying to set up HL2 with holographic emulation; works nicely with the deprecated framework but I'm not getting the articulated hands - I can see a gameobject created for the hand (right/left) but no movement. And when I switch to the new XR SDK I'm getting hands but remote window disconnects every time I stop playmode and I'm getting some strange exceptions (null reference on something called _unity_self and memory leak on native collections - with a crash every once in a while). I'd love to work with the new SDK obviously but if not then how do I get articulated hands from the deprecated holographic emulation?

 

Have no idea how to delete a thread... I've noticed there's a Windows Mixed Reality specific forum. I'll repost this question over there; if a mod can just delete this one that'll be grand. Thanks!