Hi all,
A thought struck me as I was walking back to the hotel today about my wifi issues - I had installed bind on my laptop a couple of weeks ago to get round an issue with name resolution.
Disabling Bind and allowing Network Mangler to set my resolv.conf from the supplied wifi settings.
Can't believe I didn't see it before - chalking that one up to too many things to think about at once late at night!
Many thanks to everyone for your advice and assistance :)
Jim