What is a default slideshow and how do I set it up?

A default slideshow / fallback slideshow (priority: 99) is played as soon as there is no presentation assigned to the screen in the time plan for a certain period of time with a higher priority level. So here you choose the slideshow that should be played when there is no other slideshow set in the time schedule.

You set up the back-up slideshow in Shows > Scheduler > Create timetable. Give a name to the time schedule and find the device to which you want to assign the backup slideshow by using the search function or filters and choose on which days this default presentation should be active. Finally you adjust the priority. 1 is the highest priority and 4 the lowest. Give the default slideshow level 99 .