Hi Craig,
The project created was in version 5.19. You can upgrade it to 7.19 but first need to upgrade it to version 6 and then 7.
Here is the documentation from 5 to 6.
https://docs.mendix.com/refguide6/moving-from-5-to-6
and the documentation for 6 to 7.
https://docs.mendix.com/refguide/moving-from-6-to-7
Opening the project in the newer modeler version will prompt the modeler to ask you if you want to convert it.