The current OmniPBR included with omniverse does not have heightmap support (yet). Another team member may comment on this further in this post on timing of introducing that feature. This is still early days!
Additional question: Any planned support for substance textures directly in Omniverse applications or will it only be Nvidia MDL as to stay in the realm of hydra compliancy?
We currently allow for textures to be directly loaded (and reloaded on the fly) through various connectors and Omnidrive, with this, you can setup a workflow to allow for direct export from painter/designer to omniverse and have a live update.
You can check out the tutorial here if interested: Using Adobe Substance Painter and Adobe Photoshop with Omniverse | NVIDIA On-Demand
Connectors for Substance to allow for things like generated textures from an SBSAR are in progress and we hope to have news on those very soon, along with a more refined workflow for live updates.
Machinima is still in progress :) Look for additional announcements on that in the coming month or two for how we plan to roll out the features for it!