Currently the NuGet package GHIElectronics.TinyCLR.Pins version 1.0.0 show the Pin4 in Socket 1 as 10 and it should be 26.
I could not find a place to report the bug, so I am using this forum.
I have not checked all other values, I just noticed that bug when I was testing character display and it was not working.
Daniel.