Orage creates an icon that shows the current date, with the appearance of a traditional one-day-a-page calendar. Is there any way to customize the appearance of this, especially to remove the bright orange color, but still having it show the current day?
I don't think there's a way to customize the icon. However, you can disable the icon and instead use the Orage Panel Clock to display the date on a panel and also access the Orage calendar by clicking on clock's display. Through the clock's properties, its display can be modified to include the date and/or time in whatever format you prefer. It also includes settings for foreground and background color.