The Desktops feature is only available in the professional and Ultimate editions.
On any edition you can open multiple instances of MotiveWave like Omegaknight . I have tried (I have EW Lite edition) and it works. I use Mac and I did copy/paste the application icon ran both in parallel.
The Desktop feature might still be appealing for other purposes.
To run a second instance on the mac, you would have to use Terminal. Try the following:
1. From the Applications > Utilities folder, select Terminal
2. In your terminal type in the following command: open -n -a MotiveWave.app
That should start the second instance. On a windows machine, a second instance can be started by simple double clicking on the MotiveWave application icon again.