Can I choose which Layout Elements are displayed on a subform?

You have two options to control which or Layout Elements show in a subform:

1. Create another form for the 2nd database (binding the Layout Elements to the existing fields), and only put the fields that you want to show in the subform on this new form. Or, this may be easier, make a copy of the form you already have, and remove the LEs (Layout Elements) that you don't want to appear in the subform.

Then, you will need to remove the subform element that you already put on the 1st (main/parent) database form, so that you can create a new one that displays the new form you just created in the 2nd (child) database.

2. You also can control the visibility of individual LEs by using the Visibility() command in the child form. You would use the @FormIsStandalone() and Visibility() commands in the "On Form Reveal" or "On Draw" events so that you are only hiding the LEs when the form appears as a subform.

Option 1 is probably the best solution because you can customize the LEs on the child form to influence how they will appear in the subform. This is also the answer to your 2nd question because changing colors, fonts, and LE widths on the child form affects how the subform will look.