Thanks John - i have attached my latest code, (which as you will know from my previous file, is messily written but seems to work ok). I have added in a title slide which acts to stop the loop.

There is now just one strange problem i have discovered - everything works fine, except the last "facing page" has the wrong number assigned to it - by 1. All other pages are ok. This only occurs when (if you see attached file) the last facing page is 3.1. If i remove that facing page, the rest are ok. (ie in the attached file, it will say p6 when it should be p.5. All others are ok)

Given your knowledge of loops i was wondering whether you might know what was going on here?

Thanks once again