I posted this in the forum as well, and someone else seems to be having the same problem.
When running Bryce 5 in Tiger, any File dialog seems like it is not running. In fact, it is hidden. If you activate Expose, click on the Finder, then click on one of the Bryce windows that are off screen at this point. Bryce will return with the File dialog in front (but not selected), but if you click on it, it becomes hidden again.
Hi David,
I would imagine that the version of Bryce you're running on isn't compatible with Tiger. Have you upgraded to version 5.5? (
http://bryce.daz3d.com/55index.php)
Kevin
I'll be doing that soon and will report as to its effectiveness. Obviously there is a compatiblity issue, I just didn't expect to lose one of my major apps from upgrading my os.

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Bryce 5.5 works, although there seems to be an issue with importing models, but I'll take that up with DAZ.