Trying to get the MinimalExample to work

I am new to this repositoty/tool, but I am an experienced C# developer, and I have made software for the Raspberry Pi using C#.
Now I want to figure out how to get started with this, because I want to extend my software with the capability to display the output n LEDs.
I am able to build the MinimalExample, but when I run it, I get this Error:

System.DllNotFoundException: ‘Unable to load DLL ‘librgbmatrix.so.1’ or one of its dependencies: The specified module could not be found. (0x8007007E)’

And I can see that it is the main dll in use by the RPiRgbLEDMatrix project… but not really sure how to build that… or obtain it.

/HH

I now have a working C++ installation with visual studio (NMAKE) but it has been too long since I worked with C++ (30 years) and I suspect I need to build the library to obtain the dll referenced (the missing file)

So I have tried this: