Wine currently has an issue where it won't accept mouse clicks when a game is running. There doesn't appear to be a fix from them right now - and it's open-source, so it could be years before they get around to it - so I'm working on making up my own.
Wine? I thought mac had it's own client? never mind.
I used to use SuSE Linux in the old days, in fact I switched to windows primarily for city after reviewing Wine's emulation of City of X. Apparently they got it working on ubuntu in the early days, the only real problem back then was wine wouldn't natively run other Exe files or read exterior libraries ect. when told to in the original Exe's instructions. they fixed that by telling it to do so but apparently though it ran I remember there was a graphics problem, most likely due to missing or outdated graphics codecs and missing openGL.
it was my choice, I was going to switch OSes on a spare hard drive for city one way or another (SuSE 10.0 couldn't be updated to a version with the right glibc without writing my own kernel, and because of that couldn't install the newest wine). I decided if I was goign to switch OSes for a game I was going to have the full experience, so I got on wind doze.
anyways I know for certain they emulated the mouse correctly, their only problem was the display of names in the chat system and a few costume texture errors. It might help to take a look at (or ask) how they managed to get the mouse working.
I realize this information is ages old by now so it's probably buried and I'm not sure there will be anyone around to reply, but it's worth a shot.