I can't see where it says it supports 64 bit Windows 7, but I'm positive it does. Most 32 bit applications will run on a 64 bit Windows. Microsoft's Photo Editor may be different in that it is supplied with Microsoft Office, and if you have an old Office suite, eg Office 97, that may be why it doesn't work with Windows 7.
Apparently Office 2007 does not have a photo editor component.
It's worth a try, and if it doesn't work to your satisfaction you can always uninstall it and start your search again.
Good luck.
Mark

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