I have a dashboard with a list created by a data expression and I'd love to be able to populate a s123 form from the information in that list. I don't see a way to do this using that list generated from a data expression in the same way described in this tricks of the trade article on embedding a survey in a dashboard . Is this not feasible at this point in time?
Oh, it's feasible, and something we do all the time. Are you meaning to pipe information into a new form, or use the data expression list to edit features? Both are possible.
For edits, make sure your data expression includes the globalid field so that you can include it in your URL parameters, i.e., "…?mode=edit&globalId={your-globalid}".
For new features, you can use the URL parameter field:fieldname={some_value}