Working on a converted heightfield mesh and looking to get some sort of vector displacement using a high res version.

As of now it appears that the texture baker is only doing a search in the positive direction of the N, all details from the high res that are below the low res in Y get cut off.

There's no options for the vector and tangent space vector disp exports that I can see, just a disable/enable.

Some things I've tried:
Huge range of different scales
cranking trace bias both directions
switching between true displacement and bump map displacement

the documentation says the cage mesh has to have the same topology as the low, which I can only interpret as meaning open surfaces can't have a cage mesh. Or am I reading that wrong?

I've asked everyone I know and can't find anyone that's gotten this to work

maybe post a file?

to me it looks like it traces in both directions, at least when cage is not present, however I see an issue in Ds, which seems to always return positive values even for negative ray lookup areas

Vd and Vdt however seem correct, properly containing negative values when tracing below low res surface
in case you have sculpted on the hi res and you need a proper Vector Displacement you will need to use UV Match mode instead of Trace to allow for displacements in other than ±N direction