From what I remember, IB's emini stops don't work afterhours, the reason being the market is thin enough to be easily manipulated. But check with them to make sure.
emini stop orders DO NOT work overnight. The overnight spreads can get to several points, so setting off a stop could be costly. I don't know why they don't allow stop limits, which would defend against this problem, but they don't allow any stops at this time.
I'm watching the nq trade on my Qcahrts and I don't see any level II info at all. I'm getting T&S and there looks to be plenty of liquidity. Is this a problem with QCharts? I assume there has to be a spread?
there is a 'level II' but you won't get it from the regular charting software. IB does show you the book. http://www.enthios.com/trading/market_depth.htm