Hi Debbie,
Unfortunately, I got sidetracked from this project for quite sometime so didn't get around to responding to your last post. Sorry. However, Jue_Mue did make me realise what the problem was - it was only searching the fields present in the search form! So having now read your latest post above, I hope to be able to add the fields that were not being searched as searchable fields in my config. Although as it's been a few months since I touched this project, I hope I can find everything OK!!
Thanks again so much for this - just goes to show, even when you think you can't find a solution, given long enough someone else will! Big thanks to all contributors.
Matt