Dear Otto,
1. You just need to install Visual Studio Community 2019 (2022 version is already available but we have not tested it yet)
2. Download Harbour built using Microsoft Viual Studio Community from here:
https://github.com/FiveTechSoft/Harbour_builder/raw/master/harbour_win64_ads_msvc_2020_12_25_build2.zip
3. You create a .HBP ascii file where you just simply write the names of your PRGs and the libs to link (Harbour's libs are automatically used)
Here there is an example: viewtopic.php?p=233079&sid=45fc429f4488bef75bc47a508514d5e0#p233079
My apologizes to Viktor Szakats for me taking so long to realize it. When we built mod_harbour then we really realized hbmk2 GREAT power!!!