There's not all that much documentation on the full capabilities of booktrader. Perhaps the upcoming webinar about it will discuss it. It's more powerful than IB lets on. It can actually hold its own against some of the 3rd party API apps. At least fundamentally. I didn't seriously consider it after reading the TWS manual and instead thought of buying Bracket Trader or Zero line. Turns out, IB's booktrader has all I need.
Well, it was not possible for the longest time and as someone pointed out, no updates were given. The Booktrader webinar on IB's website is not very good. I am glad to hear though that this should be working now. Thanks.