I use Windows exclusively.Essential, this is what I've trying all along. Although it works on Macs, it doesn't on Windows.
This seems to be a functional difference between how OR works on these platforms.
You should try it yourself on a Windows machine.
An understanding of opening a single instance of OpenRocket as opposed to opening multiple instances of OpenRocket is required to use the example provided.
This may be helpful for you: http://wiki.openrocket.info/FAQ#Why_can.27t_I_always_cut_and_paste_between_two_designs.3F