It's basically the same deal as using the English client to play on CWOW servers. You patch up to date, then edit the realmlst file.
I only played a trial there to see if the lag would be doable. I found that w/o a proxy of some kind, the lag was very spotty and I experienced a lot of random disconnects.
Getting time cards could be problematic if you don't want to deal with taobao.
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