If you don't click the "3 channels" in zBrush.
When ya save a 32 bit .tiff .
Even zBrush will give you a error when you try to load it back in to zBrush.

zBrush
Displacment .exr are gray like .tiffs .I think that means there just 2D.
As far as I know ya can't get colored maps out of tools/displacment maps.
Vectors .exr are colored .I think to have 3D maps ya need color.

When I get the mesh & all these maps done.
We can terrorize Pro 14 by seeing what does and don't work and have some fun :)

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The Artist that will fight for decades to conquer their media.
Even if you never know their name ,your know their Art.
Dark Sphere Mage Vengeance