Thanks for your replies. I should read the blurbs more carefully. Anyway, all is well. I use Adobe CS6. Indesign provides for export to IDML.
I'm an author and to be nice to the publishers I create my own book templates. I converted one of my manuscript files to IDML and opened it in Publisher. On a brief inspection it seems to present quite well. Will be interesting to see if has the same characteristics as the original IDD file. I'm a fan of Indesign and know it quite well but Adobe have just priced themselves out of the market. Now comes the onerous task of learning new software. Got a feeling it will be worth the effort.