No, it's not that lame.
Have you tried setting the setting the Organize/Project panel to List View and then clicking the Name column header to set it to list by name?
Given you have 753 photos that you have numbered and ordered for a slideshow destination.
What is your numbering scheme?
Where are these 753 photos at this time in their numbered and ordered fashion.
Where are you preparing the slideshow - Elements Organizer Create Slideshow Editor or some place else.
I see several doable scenarios on this, none mentioned
Premiere Elements 8.0/8.0.1...
Organizer - Organize header/Album
1. Create an Album of your numbered and ordered photos (the Album has features to achieve these purposes...note when you have an Album, the Sort Order = Album Order.
a. Select the Album and take it into the Organizer Create Slideshow
b. Select the Album and take it into Premiere Elements via the right click command Edit with Premiere Elements
The photos should stay in order in "a" or "b".
If you have your photos in a folder on the hard drive (numbered and ordered), then import the whole folder into Premiere Elements with its Get Media/Files and Folder and drag the whole folder to the Timeline....the photos will present on the Timeline as numbered and in order.
If you have 753 photos, what is your numbering system 0001 to 0753 or something else?
My usual drill for Premiere Elements 8.0/8.0.1 users...
a. Is automatic Background Rendering and AutoAnalzyer Turned Off
b. Are you working from the 8.0.1 Update of the program?
c. Is the Enable GPU Playback in preferences the correct one for your video card/graphics card which we assume is up to date according to the web site of the manufacturer of the video card/graphics card.
d. What are the pixel dimensions of those 753 photos?
Let us start here. I know the above works for me. Let us determine if this works for you also.