Hi Graham.

Xara has officially retired MenuMaker, they no longer officially support it and they suggest that you try out Xara Web Designer, in which you can build your entire website, using modern HTML standards and without without dealing with html code. There is a 30 free trial on Xara Web Designer, so you may want to try it out. Perhaps seeing how Xara Web Designer does it will give you the clue you need.

That said, I believe it should be possible, but I haven't used the product in years and I don' remember for sure how to do it. I'll see if I can find someone who can answer your question.