An open access author-accepted version of the paper (complete with very inconsistent spelling of 'Pangaea') can be viewed for free in the White Rose repository here: http://eprints.whiterose.ac.uk/161099/.
This repository contains all of the code used for the paper, and the data which I downloaded or processed (so doesn't include additional data I was given for the modern LDGs or the oxygen isotope curve).
In the 'Data' folder you can find the Late Permian, Early Triassic and Middle Triassic traces I drew from the Scotese basemaps; you are welcome to plot your own data on these but I would appreciated being acknowledged for them!
There may be slight discrepancies between the code as posted here and the code in the data supplement on Dryad. You can also find a version of the SQS and Squares code which is slightly more extensively annotated in the workshop I co-developed for Progressive Palaeontology 2020 (see other repository).
If you have any questions or problems please get in contact with me! My email address can be found on the paper.