From the User Manual, maybe this answers your question:

Transitions in Storyboard Mode You can open the transitions menu by simply clicking on the transition symbol between two individual photos.

Here's where you'll find all of the transitions that MAGIX Xtreme PhotoStory on CD & DVD 8 has to offer. Simply select a transition. You can also choose the length of the transition. "Apply to all" applies the setting to your entire slideshow. Additionally, you can set random presets for each transition ("Random Transitions") or apply the selected preset to all.