1. Unpack the mod that adds new sectors.
2. If this mod in Steam, unsubscribe.
3. Delete cat/dat files
4. Make changes to the file libraries\region_definitions.xml (Example you can see in my mod)
5. Pack to cat/dat as desired (the mod should work and in roaspakvanomu form)
6. The program for working with cat/dat files can be downloaded from Steam X Tools, in the Tools section.

Comment out the parameters :
volumetricfog

Change parameter :
/fields/nebula/localdensity to 0.0