Thank you!
To set this up, grab my Area Command script and open its config window as described in the post about it.
You'll want to define two areas, one for each monitor.
If you want to open two different layouts, the commands for each area would be like this:
Prefs LAYOUT="My Layout 1"
...changing the layout name as appropriate.
The linked post also has a section on the setting to change to make desktop double-click run the script, which you'll want to do.
Let me know if you hit any snags or need the script expanding in some way.