PSE12 typically represents Photoshop Elements 12. There is no video editing in Photoshop Elements 12 (photo editor). There is in Premiere Elements 12 (video editor). What computer operating system are you using?
Premiere Elements 12 project supports video and still imports into its project.
And what do you mean by "loop"? There is no looping feature in Premiere Elements 12 export to file saved to the computer hard drive or burn to disc.
The Premiere Elements 12 project allows for one project preset and that is based on the properties of your major file. If you have more than one
format or file type then you fit the rest into the project settings as best to can to achieve the wanted effect.
How many photos and what pixel dimensions for each?
What is your destination - burn to disc DVD-VIDEO on DVD disc, AVCHD on DVD disc, or Blu-ray disc format on Blu-ray disc?
With more details, we can fine tune and customize a reply.