I created some Custom Fill Patterns by importing the different pat files into Revit. Works great. At the export pattern mapping I use a similar PAT file to generate a good DWG file. However, for some reason the hatches in AutoCAD are called FP_* (asterisk is a number starting with 1). I checked the AutoCAD options, and the path to the pattern files is correct. How can I generate a DWG with the correct hatch names (instead of FP_1)...
I had a Revit project that works fine. By using Transfer Project Standards (DWG Export settings) I was able to transfer the right export settings. Now, the correct names are shown in AutoCAD as Hatch patterns.
Unfortunately, I do not know what went wrong still.
Further researched it. The fill pattern that I exported now, was a simple Revit one. Not a real CUSTOM pattern. So, Revit translates the pat-file to possible Revit fill patterns. If that not succeeds, it will use the custom pattern setting. However, that is not working properly