You may need to use the Advance Options settings of Monarch/Modeler to trap multiple lines. If you want, you can email firstname.lastname@example.org so we can open a ticket for you and replicate the issue.
You may want to open Lesson4.dmod with Classic.prn in Modeler. These are sample files that come with your Modeler. Go to Report Design and check out Customer_Full field in Customer Level template. Click the "Edit Field" button on top of the trap line and it will show you the Template Properties. Go to Advanced tab.
That is an example of how to capture multi-line data using a single sample line.
Hope that helps.