I have the trial V2. Is there a way to select all JPG images and increase their duration (increase the number of seconds between images)? Any other slide show tips?
You can change the duration of an image by grabbing the right hand edge and dragging to the right to increase it or left to decrease it. I don't know a way to change the duration of all of them in one go.
As for slide shows in general, have a look at what you can do with pan and crop - a bit of movement adds a lot of interest. I'd also consider putting a music track down first and then timing the slides to fit that.
If you're going to use naration, plan and practice it carefully - it's amazing how many people develop amnesia, dyslexia and get tongue tied when they've a microphone in their hand.
Sound effects can add a lot, too, but be very careful they don't become obtrusive. If you want to add a bee to a garden scene, for instance, it should only just be audible.
If you select all the images you can then Ctrl-drag the end of the last one to the left to shorten them all or to the right to lengthen them all at the same time.