Aslak Kjølås-Sæverud

You need to base the Pop Object's Creation Frame on the live tick instead of frame number.

1. Set Creation Frame to ch("../continuouscook_tick")==0
   
2. Enable Live Sim on the DOP net
   
3. Make sure Live Tick is at zero
   
4. Enable Live Nodes in your houdini session
   
5. Do step 1 & 3 if you add other dop objects to the sim.
   

This seems to be because sop -> usd does not like packed pivots. Here is a slightly cursed solution, "removing" the packed pivot.

edit: Enabling Calculate Spin per Wheel on rbd follow path also seemed to help

I assume you've read the karma lens docs? https://www.sidefx.com/docs/houdini/solaris/support/karma_lens_shader.html [www.sidefx.com]
There are some sample files that make use of custom lens shaders, they might shed some light on how to get it to render to disk.
I feel like it was working when I was playing around with a custom lens shader in h20.5

edit: Here is the one that I built, also using vop nodes https://www.sidefx.com/forum/topic/94084/?page=1#post-424757 [www.sidefx.com]