Issue when running "go get"

[ovehro]

I tried to run
go get github.com/mcuadros/go-rpi-rgb-led-matrix
on my pi, just as in the readme.
But instead of the expected error, I get
src/golang.org/x/exp/shiny/driver/x11driver/screen.go:20:2: import "golang.org/x/exp/shiny/driver/internal/x11key" is a program, not an importable package
I don't understand how I should fix this. Anyone there for help? Thanks

Also: When running on my regular machine under Windows 11, I can setup everything correctly. Until I try to run. IntelliJ marks everything as correct and I also get autocomplete. When I try to run I get:
.\main.go:16:20: undefined: rgbmatrix.NewRGBLedMatrix .\main.go:16:47: undefined: rgbmatrix.DefaultConfig

Is it even possible to run under Windows? Of course with the Emulator. I would need this for Development Purposes