For #2 - You can use either UWP or WinUI for Windows 10/11, and then you can use several options to 'back port' UWP/WINUI features you are using to Win 7 (PWA, Electron or Skia - https://platform.uno/windows7/) . This is because WinUI is not supported on Win7 and Uno Platform is the only way to 'back port' do it. You cannot use WPF with Uno Platform.