Customizing Scheduler Appearance
The Schedule element uses a "template file" to define certain element properties that are not otherwise available as attributes to the developer for modification. These include language- and culture-specific Caption attributes that you may want to change for locale-based reasons (or you may simply want to change the captions to better suit your application).
The element's Template Modifier File attribute identifies a custom XML file developers can create containing special tags that will override elements in the template file, changing the appearance and some functionality.
More detailed information about template modifier files can be found in Template Modifier Files.