Thanks everyone so much for your input. I am so sorry not to have got back onto this thread - I just had time to read it before going to the shop, and then we went away for 4 days to somewhere with no internet/mobile coverage!
Be assured that I took all your thoughts (even contradictory) very seriously!!
I decided in the end to go with dress #3 (pic 6-7) I tried it on again and the fit was perfect, as opposed to the floral strapless one which would have needed alterations. Those 2 were the frontrunners as they were from a shop which does returns. So I won't take the tags off in case I find something better in the meantime, though this is not that likely as I won't make it up to the big smoke before the wedding!
I am now looking for coverups, and keen to hear of any leads for australian sources for metallic (or maybe white?) cardis, jackets or trenches.
Unfrumped I am not sure of temps in the evening but the historical average for that day of the year is 13-29 C - I am guessing it could get down to 16-18 C which I'd definitely need something on top for.
PS I wish, Janet and Shiny, that my lifestyle did include ops to wear dress #2!!
