Windows 7 emulation turned out the toughest of all in the long run. The odd bits and pieces found on the net appeared to be either incompatible with Gtk 3 and/or Cinnamon 2 or ugly and misshaped. I almost gave up but finally was able to stitch two larger pieces (window decoration with controls and Cinnamon panel with menu) together and fix numerous glitches in theme coloring, metrics and placement in Java scripts and .CSS files into a nice-looking
Windows 7 Basic emulation. As a side effect, I've also fixed main menu misplacement in the former Windows XP and 8 themes.
Windows 7 Aero will be a real challenge because Cinnamon 2 is incompatible with either Compiz or abandoned Emerald nor does it have built-in support for blurred Aero glass emulation. But who knows, who knows...