First of all, a really nice control.
This is only posted as a help to ppl.
I think it would make more sense, to only have panels resizing below the children hirarchy of the selected splitter. Specifically I need a layout to be adjustable, and did not want to se resize width etc. on every new creation of a resizepanel.
In ResizingPanel change i = 0 to i = iSplitter - 1 in the two for loops on line 999 and 1014.
But anyways, a really nice control.