I have a lowres object with UVs here, and a matching highres object with some displacements sculpted in ZBrush. Both are in the same OBJ file, they import into Toolbag just fine using the Quick Loader.
Baking all the maps works without problems, normals, curvature ect. all look as expected, so there doesn't seem to be any problem with the objects themselves (?).
The only problem is the height baking, it just doesn't work at all. It outputs a map, but it doesn't have any (different) color values in it, its just plain grey. Loaded into a 3d rendering app the surface just displaces outward very evenly everywhere, meaning there are indeed no different color values in the map.
When I edit the height settings in Toolbag (inner/ outer distance) to anything else but the default (-8.0 / 4.0), the exported map doesn't even show a recognizable UV layout anymore (the space between UV islands would be darker in color beforehand). It is just an image of pure, plain grey. Something seems to be wonky here in the baker.
I rarely use displacements, so it might be (probably is) user error, something really obvious.
What could be going on? Is there a problem with height baking in Marmoset Toolbag, or is it me?