According to Adobe document, Premiere Elements 13/13.1 does not support Windows XP, Windows Vista, and OSX 10.7.
According to Mac System Requirements - support is for 10.8 to 10.10.
If you want to get a return/refund for your product, please see instructions in following
This is not Adobe. Rather user to user. This is an Adobe matter for which we have no control. Please discuss your situation with Adobe since Adobe is only selling 13 as download..It would seem that you want to explore an earlier version of the program, you will have to seek another vendor to find out what earlier versions the vendor might still have in stock.
But, first get Adobe's perspective on your situation.