themes: no .msstyle file type association

When theme service is not running, double click on *.theme file. ReactOS will ask you to choose program to open file with (Open With dialog will appear). Windows XP will tell:
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Error Loading Theme
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The theme could not be loaded because the theme service is not running. You can turn the service on in the Computer Management Administrative Tool in the Control Panel.

File: C:\WINDOWS\Resources\Themes\Royale.Theme
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OK
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When theme service is running, double click on *.theme file. ReactOS will act the same. Windows XP will open Display Properties with selected theme.
r54209