Open ghoh.sln in Visual Studio 2022. It needs the Project templates for Rhino 3D extension and Microsoft.NETCore 7.0.11.
Minimal viable example for position fetching from an open haptics device:
Tested with Grashopper Build 1.0.0007 (2023-12-12) in Rhino 8.2 and Open Haptics v3.5 on Windows 11