Hi Christian,
Have you restart your computer after the installation process?
Do the error messages are prompting the same thing with your first one?
I have looked internally and found this from the engineer.
To debug this, ensure WSL is installed correctly on the Windows machine and you can test this by launching Nios2 Command Shell.
Done.
Next step, it would go to the IP owner to determine if they are invoking Nios2 Command Shell correctly.
In all scenarios, Qsys merely evaluates what's written in the IP's HWTCL file. If it fails when attempting to run something from the IP's HWTCL file, it is most likely something not working within that IP.
Can you identify it?
Regards,
Adzim