Missing win32_platform.h from GLFW at compile time Solution
I solved this issue but wanted to mention it for others on Windows 10.
Have choosenim 0.4.0 installed.
Installed nimgl via nimble :
`Nimble install nimgl.`

Run your green window example (via VS code)
Get this error ..
`.nimble\pkgs\nimgl-1.1.0\nimgl\private\glfw\src\win32_platform.h:69:20: fatal error: dinput.h: No such file or directory`

To fix follow these instructions  (which updates gcc version from here https://github.com/dom96/choosenim/issues/129#issuecomment-541207506).

```
Delete %userprofile%\.choosenim\toolchains\mingw32 folder
Download https://nim-lang.org/download/mingw32-6.3.0.7z
Unpack it into %userprofile%\.choosenim\toolchains\
gcc --version now prints 6.3.0
```

Green window example now runs.