Hey,
You have a level blueprint set up to change the quality of your project. I deleted all of those nodes, changed the settings back to epic, used the save all that’s located within file. Then I went back to where your project was saved and deleted all folders except for Config, Content and the Unremarkable.uproject. This way it forced your project to rebuild the settings. Once I did that, I opened the project back up, made sure the scalability was at epic (or auto) and saved it again, then ran the project in PIE and all worked perfectly.
Please let me know if you’re not getting the same results on your end. Looking forward to hearing from you!
Thanks!