Thanks for the response.

The document was created as a pdf file in MacPages and converted to .docx file in Adobe Acrobat.

Since posting the query I imported the .pdf file into Word, which did the conversion to .docx. The problem with text boxes has disappeared, but the fonts have changed and will need correcting. The images are displaced a little, so will have to bone up on image selection and moving.

Will see how we go.