Heres a working example of your code. It only took minor changes to get it working. I've added comments where I made changes.
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# The original example had the grid way off to the right. This was causing
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After your last e-mail I got confused (you got the code working, mine didn't
work) and investigated until I discovered that the horizontal scroll bar
doesn't cause scrolling. The cells were truncated and the expansion 'buttons'
were not visible.
Thanks.
art
