Add new SlideShowXMAS Theme

A new Christmas theme has been added that shows random Christmas images with an animated transition between images.

To switch to it on the Main Menu choose Setup then Theme Settings and change the 'Theme' setting to SlideShowXMAS, move to 'Save' and press 'OK'.

NOTE you may have to restart MythQML for the theme to reload properly.

A screen shot of the new Christmas Slideshow theme.