I've been away from the forum for awhile, but have come back, and have a new outlook on several things, including this specific topic:
I have had so many guys back out of deals they committed to, that I actually stepped away from cues for quite awhile. (that issue and a few others) I will, from now on, be leaving negative itrader for "buyers", that commit to a deal, and then back out. People who have to deal with them in the future, need to know that they may back out.
Because of all the escrow I handle, on top of all the deals I have done personally, I have heard and witnessed every excuse possible and imaginable.
P.S. I have dealt with Zhou a few times, and never had any issues that I can recall, but that does not mean that this should not be in his itrader.