[moved to premiere elements forum]
First, how did you create the SlideShow, that you now have in PrE?
There are several workflows, and it might depend on how you created the SlideShow.
For a Title, even with one of the Animation Presets, you can extend its Duration (it will be created to the Duration set in Edit>Preferences>Still Duration), by click+dragging on the Tail. That will slow down the Animation.
Also, one can use Keyframes to Roll/Crawl Titles with the Fixed Effect>Motion>Position. With Keyframes, you can also pause, or hold a Title, for as long as you wish.