Thanks for the quick response!
What you're saying about the material properties is what I thought but I did not find any examples with workbench in combination with a usermat so I was not sure. This is basically how I do it right now.
To number 1) this is what's included in the link_error file. Actually both files (link and error_link) look the same.
2) yes I am using the oneAPI 2022 since we couldn't get a hold of the old versions and everything worked up until now.
I tried to find the location in the ansupf.bat file where I have to include what you proposed but I'm not sure where it belongs. Could you give me a hint?
Besides that as you are familiar with WB and UPF: right now I compile everything in the ansys...\winx64 folder and have my ans_user_path variable set to the same folder. Is this the correct way or do I have to include the usermat.f in the solver files directory. I read somewhere that usually it should be put there and the compilation process starts when solving the model when all variables are set correctly.
Thank you again for the response!