I completely see what you mean, Emma. I wonder what would happen to my book if it ever came to this? My character is British and moves to the USA, and her language gets ever-so-subtley more American as the book goes on (so subtle that I'm probably the only person who'd notice!) I'd be heartbroken about changing that. Of course, I'd probably be too thrilled at being published in the US to care...
'ciggie ash' sounds like a good compromise. At least it has that 'ie' thing which is very British/Australian-sounding.