For those of you researching new brokers and/or thinking about switching over to IB (or perhaps just did and you're still learning their platform), IB just released an updated version of their TWS Tours app for the iPad that includes a nice section on Mosaic. I just watched the TWS and Mosaic "tours" and they were very helpful pointing out a couple of customization tips that I hadn't seen yet (TWS is SUPER customizable for those of you that want to pull all the levers behind the curtain). If you have an iOS devise and want to check them out, you can find a link to these here -->
http://www.interactivebrokers.com/en/p.php?f=tradersu&p=tours
and their web based tours here (which I did not find as helpful as the app versions but maybe they've updated them since I last viewed them)-->
http://www.interactivebrokers.com/en/p.php?f=tradersu&p=tours
Enjoy!
Yeah, it's goofy that IB complains about that. TOS has no problems w/me having buy and sell orders open on the same time on the same trade.
I've found that it's less work to Pause Execution (right click on the order), place your opposing order, then click Transmit.