Windows API design

[frankly]

Oh thank you sooo much for your reply, Roderich, I'm very desperately to get some replies bcoz I'm totally stuck here...

I think that FindWindow thing is quite interesting bcoz I don't think I'm gonna modify those codes for the 6 programs bcoz they are supposed to be like this...and this GUI is only trying to let ppl to better understand what I'm doing. Like if I integrate the codes of these 6 programs, it will lose the orginial purpose and meanings.

So I'll try to avoid making and changes. As little as possible I mean.
So I have to use FindWindow in these 6 programs to ge the handle first? Is it the child's handle? hehe sorry for the stupid questions...me very new to Windows API