Have you ensured that all of your photos are no larger than 2000x1500 pixels in size?
Which version of the program are you using and on what operating system?
Premiere Elements 12 will add a batch of photos to your timeline in alpha-numeric order, which may or may not be the same order as they appear in Lightroom.
As you have 200 photos, you will need leading zeroes in the names of those below 100. i.e. 001, 002, ... , 010, 011, ... 099.
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What version of Premiere Elements are you using and on what computer operating system? Information needed to give you version specific details if necessary.
However you do it (numerous ways), consider assuring the order of the photos in a folder before you attempt to import into Premiere Elements. And, then when you go to import into a Premiere Elements project, import the folder containing the ordered photos, not the individual photos. Finally drag the "folder" from the project media bin to the Timeline where your photos will present in the order.
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