I have come around the Post regarding SuperPanel and was kind of upset it wasn’t that what I have been searching for. Also the perfomance is a little sucky (never mind ;) ) So I thought I have to do it better - this is what I made out of it

You can add new Windows by Pressing the button, it will react exactly as you would expect it from a windows window. Double clicking the header will expand/shrink the window. If you collapse it it will set down to the bottom of it’s container. Please let me know what you think of it and I will release the source code. As you might guessed you can also resize the window by dragging the right lower corner. Al l graphics are drawn via code but this can be easily changed. There are Methods to let it come up expanded or shrinked, an initial size and position and much more.