If while digitizing a form that you need one or more new fields or other field/table schema changes in your target Quickbase, you can add them in Quickbase, make sure you have Saved any work, and then refresh your Form Engine browser window. The new field(s) will now appear for use in your form.
If you delete fields in your target Quickbase that are used in your form, the placeholder will stay on the form (shown as “Loading…”), and the form will remain usable. The deleted field will just not appear on the form when the form is used.