I’ve updated the FInstagram sample to use the new Relation columns in the Data Editor.
You can make a read-only copy of the user profiles by mirroring the Profile sheet in another tab, but this is a bit too advanced to include in the template.
Create a second tab in your sheet and put in cell A1: ={Profile!A:Z} to create a copy of the profile sheet. Now use this as the read-only profiles in the app that cannot be edited.