On your main screen,
click on EFFECTS tab,
click on VIDEO EFFECTS tab,
select and click on SLIDE SHOW.
Click on OPEN, find and select the specific folder with the JPG you want to show (what ever is in the folder [everything in it] will be shown) and highlight one JPG file,
Click on SLIDE SHOW,
Select SLIDE SHOW type (I use SMOOTH)
Move the slide bar to set the duration on each JPG in the folder (left is fast, right is long)
Click ACTIVATE.
Also, in SETTINGS, then VIDEO, you can select SLIDE SHOW in the USE THIS PLUG-IN FOR AUDIO ONLY FILES so that when a video is playing, it's on the screen, but if you select an mp3, the SLIDE SHOW begins automatically. I generally have a folder of two or three small logos which seems to work nicely.
This SLIDE SHOW feature is also helpful to present announcements, welcomings, et al.