You might find
https://www.gmayor.com/insert_content_control_addin.htm a more user friendly means of inserting content controls and FWIW I would suggest putting the different coloured header outside and above the content control rather than leave it to the user to format.
Looking at the content of the control, frankly I don't see the point of it here. This should be fixed text and the content control used for collecting the user's input relating to that content.