These are the command line switches that are passed to the screensaver for different things:
In 'Screensaver' dialog, viewing the screensaver in the little fake monitor thingy:
/p 67496
(Where '67496' could be any number - haven't figured out if this is a hWnd or a hDC yet. Basically, if you get passed this switch just quit or show a little neat window somewhere, unless you can use this value.)
Settings: /c:329620
(329620 again could be any number. You don't need the number. Just show a settings dialog. When this terminates, the '/p whatever' switch is fired again.)
Run/Preview button: /s OR /S
As it says, /s or /S.
I think /s is used if it's just the 'Preview' button clicked, and /S if the screensaver is started by being double-clicked on, or started normally by Windows 'cuz the system's idle.
Again, I'm not sure, but I think that if you set the 'time' thingy to 10 minutes for example, for every 10 minutes of non-user interaction that passes your screensaver gets started again - so check to see if it's already running...
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