I have a model that contains the append tool. The field map populates fine and provides options for making adjustments when I run the model from the workspace.

However, when I run the model as a tool, the field map options are not available. I cannot make any changes.
Same model, same inputs, but run as a tool from the toolbox: "Add New Source" (circled) gives me no options.

Works fine in ArcDesktop.
Thank you,
Randy McGregor