William Harley

This is how you add blendshapes to the mesh.
https://www.sidefx.com/docs/houdini/character/kinefx/blendshapes.html [www.sidefx.com]

This is the standard way to add blendshapes to a character for kinefx and Apex.
In the apex rig use the blendshape component,
https://www.sidefx.com/docs/houdini//character/kinefx/rig_components/blendshape.html [www.sidefx.com]
it will automatically pick up the blendshapes from the mesh and create sliders for them in the viewport.

You can change the look of any control using the configure controls node. The second input on the configure controls can be used to add custom shapes.

The configure controls can also now completely unpromote unwanted controls, cleaning up the channels.