What is your Aperture version? Is Mac OS X (10.3.x) still correct? I thought an iMac would at least require Mac OS X version 10.4 Tiger?
Even though the photos are in the main project, they will not show in the smart album by date - the dates are on the photo, but for some reason, the photos don't show.
That may have several reasons. It takes awhile for a smart album to be updated, so the images may not show immediately. And the source of the album may be set to a different project. Check, if the source of the smart album is set to "Library" and not to a single folder or album.
What kind of smart rule are you using to restricct the Date? A "Date" rule or a Calendar" rule? A "calendar" rule is easier, because you do not have to enter the date in exact the right format.
Actually, I'm running OS 10.8.3, so I will update that. And Aperture is version 3.4.4
So it's been a few hours and the album still hasn't updated.
The source of the album is set to Library then project 2010 (the project the photo has been placed in) and then iPhoto Library. So I think based on what you're saying this is where the problem lies. Is there a way to remove the third source of iPhoto library?
And the smart rule is a Calendar rule.
The source of the album is set to Library then project 2010 (the project the photo has been placed in) and then iPhoto Library.
It is hard to tell in the screenshot, but if you click "Library", then the background will turn darker and the source will be set to "Library", even if the other options are still listed to the right of library.