The displacement fixer algorithm has progressed and evolved. Various problems have been dealt with and it appears to be pretty solid right now.
Displayed here is the algorithm used in an actual project rather than just a simple testing environment.
The manual will have a deep explanation of how to use it, it is very easy but you need to comply with the way Octane works.
To make sure your heightmaps work the right way, Phantom Architecture will also feature a function where these will be automatically fixed to span the right color range. Pop in the heightmap and it auto-exports a corrected one.
The pictures in this post show the result (displacement applied), the wireframe model (without displacement applied), source model in SketchUp:
The displacement really has a great effect on the way the architecture is intended by the designer