Hi Evan,
Thanks for the project file. Indeed, PVsyst has a problem with the "Shadow Casting" setting on PV fields. According to the documentation (https://www.pvsyst.com/help/project-design/shadings/partial-shadings-and-calculations.html?h=casting#shadow-casting) this setting should not prevent PV fields to receive shadows from surrounding “shadow casting” objects.
I have raised a software change request to address this issue. In the meantime, please turn the shadow casting for all your PV objects ON (setting by default). Cannot really think about a scenario requiring the shadow casting of PV trackers field tuned OFF anyway.
As far as I can see non-PV Objects behave as expected, they cast shadow on PV fields according to their settings.
Best regards,
Eric