Two years ago we searched for a solution to migrate existing 4GL-database-programs to GUI's. First, we discussed a cross-compiler to translate 4GL into another database-language with builtin GUI (New Era, Powerbuilder, Gupta a.s.o) but this would exclude expierenced 4GL-programmers from the development. Therefore we decided to write a source compatible compiler.That produces programs with a configurable, flexible GUI-frontend. We choose Tk for the remote GUI, because we had some experience with it (usaging it for visualization in measurement tasks under Linux/X11), and it was free. The only problem was a good Windows port for the actual Tk3.6 version, because the majority of customers were expected using Windows (especially in Germany). We took one 16bit-port from Software Research Associates Inc. and started development at the Win32s platform to support native controls, sockets, optimize speed, and eliminate bugs. We call this Tk derivative WTK and it's of course freely available with all sources. See more information at wtk.html. Of course we want to switch now to the main distribution, to use all the very nice features of Tcl/Tk8.0, but there is one reason , which doesn't allow us to use it: performance.