Hi Dave,
I've tried all sorts of testing and not been able to narrow it down. Your idea about starting with 2010 from scratch is one I do not think I have done and is a very good idea. However I have mainly wanted to fix it with existing drawings

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One thing that I noticed yesterday that is really weird is that if I take a drawing that in Visio 2010 has several foreground pages set to various background pages, when I take the drawing and open it up on a computer running 2007, those foreground pages are set to completely different background pages!
I opened up 2007 yesterday and started working in it and it is amazing how quickly we adapt, as I was now moving slowly around 2007 because I have so thoroughly adapted to 2010. I like 2010 a lot better, but anyone who uses it needs to be prepared to at first waste hours looking for where new commands are, some of which are not only moved by totally renamed! And as usual MS spent a lot of time working on fluff and didn't fix core things people have asked for for year after year, like being able to paste an object from one page to anther and have it appear in the same place. But now I am ranting, and it's probably not reasonable for me to expect them to fix those things after 5+ years of new development and hundreds of millions of programming dollars spent upgrading Office

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David