Welcome to the forum, AJW.
In Xara3d7 typing text, when you hit Enter, you start a fresh page. Use Shift-Enter to start a new line within the same page. You cannot see all the pages at once in the main screen. Use PageUp and PageDown keys to see the different pages.

If yo wish to edit text in the main screen, you must activate the cursor, by clicking on the a|b button, then positioning it to where you want to start typing. If no cursor is showing, then what you type will replace anything that was there before.

The Text screen is specifically for text, if you want to do other things to it then this must be within the main screen.

Mike