Try using the system class (http://docs.rhomobile.com/rhodes/device-caps#system-class), if you are running the RhoSimulator with a version a windows I believe you should get Win32 as the device name.
Simple code to add into a erb page to test.
<li><%= System.get_property('device_name') %></li>
Al great! That works like a charm. We tried using the 'platform' property, but that didnt work since it returns android on the simulator (since it uses the android rhosim).
Thanks for the answer!