Thanks guys, sorry about the lack of code tags !

It turns out they won't need to enter any data into the combobox, it will be sufficient just to have a none of the above option.
I can then use conditions to select which text shows up at the bookmark, it won't actually need to be the text that's selected in the box, just some disclaimer stuff. So I think I have it worked out now.

Thanks macropod for the bookmark updating code, I hadn't tackled that yet as I was focused on the first problem so that will be very educational.

Cheers guys, thanks for your help !
Regards,
Dan