And QlikTech is really sure that V10 publisher will be able to do this ?
Well, you could do this in .NET (C# or VB), e. g. the main program could launch parallel threads for reloading A,B,C,D (these would be the child processes of main program), and reload for E would only continue if there are no more child processes (meaning A-D reloaded).
Actually with .NET you have a lot more of possibilities than with batch or even VBScript, and the scenario being rather complicated, I'd do it this way. I've done a similar task in C# which runs very well (parallel data reloads, and when all data reload threads have finished, starting parallel application reloads).
That's only a rough sketch and I haven't thought a lot about it, but I doubt if you succeed with batch or VBScript.