Oops, just discovered a flaw (probably one of many to come).
The form is designed to represent an A4 page in portrait mode, where
basically the bottom two thirds are occupied by one large textbox.

If I go into this textbox and keep pressing Enter, I can get to the very
bottom of the textbox and I can enter text.

But if I then press Enter the textbox scrolls up the form,
giving the user the impression that the textbox is expanding to meet the
user's needs.

Can I stop this, please?

Regards.