My withdrawal just went through and Joe sent me a satisfying explanation.

I'm locking this topic as the issue is resolved.

Thanks BTC.sx.

Has anyone else been able to withdraw from BTC.sx in the last week?

That's good to hear. If the problem gets fixed I'll update this post immediately, but right now the withdrawals are still stuck and I haven't gotten a email reply in days.

If you check their facebook page, other people have the same problem:
www.facebook.com/btc.sx

Thanks- I'll msg Seal.

Were you able to withdraw in the last 6 days? I was able to withdraw before that, but not now.

BE CAREFUL OF BTC.sx !  

I tried to withdraw from BTC.sx 5 days ago, and it hasn't gone through yet. I've emailed their support several times and received one response days ago, which said my account was "currently locked pending further investigation". I've seen several other posts that also describe similar experiences.

Has anyone been able to withdraw from BTC.sx in the last 5 days?

Be very careful: I would not make any deposits unless you're sure you can get your money out.