I was having issues with back-fill and contacted qt support @ TD.
They said:
"QT is currently in the process of being drawn down. The tentative date for this is June 15th, 2012. A business decision has been made to cease support and maintenance of QT, so we are trying to integrate as many...
just get "AmiBroker";
You can use AFL (very much like c) or use what-ever language U want (through scripting or OLE) and its is FAST!
...and very inexpensive...