ZBrushCentral

Losing highest SubDivision density after creating UVs and Zbrush reprojection crash?

I am encountering something that is probably a serious bug.

I am working on a very high poly model which is about 65 Million polys. I have 8 subdivisions

So I discovered that I forgot to create my UVs. So I go to UV master, create UVs on a clone, then paste these UVs on my lowest subdivision.
Now once I reach my 7th subdivision the polygons are around 16million. But once I shift to my highest Subdivision, it also shows the same polygons and my total Points from 65Mil are 16Mil in both 7th and 8th Subdivision. Basically I am losing the 8th sabdivision’s original polygon density

What is going on??

Also i tried to solve my issue by creating a fresh low poly model with UVs to reproject my details on BUT:

whatever I am trying to do with the model that involves reprojection, Zbrush crashes and sometimes it gives me a bad_module error but not always. Most of the time Windows tells me that the exe stopped working.
Reprojection efforts involved:

  1. Creating a low poly mesh, subdiv and reproject the details of the original on the new subtool
  2. Adding an edge loop with Zmodeler after freezing the subdivsions
  3. Remeshing any part on the model
  4. And just discovered that by simply freezing and unfreezing, the program crashes

This is very very annoying and I have wasted hours experimenting without any solution.

Does anyone have an idea?