Hello fermata,
(For our reference, error 0057 is "Could not create the folder ...", which will probably be due to a file/folder permissions issue.)
Did you have any version at all of Hauptwerk installed on this computer prior to running the v6.0.1 installer? Which version, if so? Was it running successfully on this Mac under macOS 11 ('Big Sur')?
If you didn't previously have Hauptwerk installed on this Mac, when you set the Mac up, did you use macOS' function to transfer your settings and programs from another Mac? (Doing so can result in a partial/broken Hauptwerk installation.)