How to reproduce: test the attached project with the latest version on a Windows 7 machine, notice that the font sizes are scaled, test the project with assemblies before  R2 2017 the fonts are not scaled

The issue is observed even with the RadControl.EnableDpiScaling property set to false. It would be expected that if the property was set to false, that the fonts would not be increased.

Workaround: change the fonts for each of the controls individually, the scaling can be calculated this way:
  Protected Overrides Sub OnShown(e As EventArgs)
        MyBase.OnShown(e)

        Dim dpi = NativeMethods.GetSystemDpi()
        Dim scale = dpi.X / 96.0
    End Sub