Vala Gtk+ Windows egs?

I am trying to learn Vala to create cross-platform (Linux + Windows) GUI applications.

So far, for Linux everything “just works”. The only real problems are out-of-date docs and out-of-date examples (e.g., showing deprecated things that either won’t compile or output deprecation warnings).

But on WIndows using msys2 although I can get a window with buttons up and running I can’t load any icons from the filesystem or figure out how to use built-in ones. For example see my other post Learner having problem with hello gtk eg

Can anyone point me to a small pure Vala GUI project < 2000 LOC that uses modern code and runs on Linux and Windows so that I can get some idea of how to solve the problems with icons?

Or can anyone refer me to some up-to-date documentation that tells me what I need to install on msys2 to get a fully usable environment for building Vala GUI apps? (This page is only adequate for creating console applications.)