Hey @elkhiar and @anon78309838, I am stuck in exactly same situation… I am working on app where users will “give” or “ask” for items.
I want to automatically set the item category to “givng” or “asking”, so I have linked the action button to a modal - where a user would select “give” or “ask”, and then get directed to either “giving form page” or “asking form page”. It all works fine but when I try to set up automatic field to select either “giving” or “asking” category, I don’t get the option.
Am I missing something obvious or is it a bug? Please help 
Screenshots:
Create New Item Form
Automatic Field: Category - Empty, Value Empty
Database setup:
