In the XML where you are defining the size of the window (under "<ChildTmpl/>") you have width and height (this resizes the child window for you), just add left and top there and it will move the window into the position you want so it looks centred in the parent window, I am quite sure. Sorry for not being overly confident on this one but I usually get Jay_Jay to do my windows
and I don't have the scripting documentation at uni. Have a look in the XML schema thing there (the bottom one all the way through) and if you have a look at the different adjustments you can make and compare them to what you have in your XML you should start to notice patterns and understand how the schema documentation is set out for future reference (don't worry it took me a while to understand too
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