After much searching around without getting anywhere, I stumbled upon an easy fix to make Aperture run on a MacBook without nagging you that your screen is too small or you have too little RAM.
Control-click on the Aperture application in the Finder and pick Show Package Contents from the pop-up menu. In the Contents window that opens, edit the Info.plist in the Property List Editor (Developer Tools required.) Change the following entry:
AELMinimumRAMSize string 1000
Change 1000 to 512 (if you only have 512MB of RAM). Also change this line:
RKMinimumDisplayPixelHeight number 854
Change 854 to 800. Save the file (you will need an admin password) and relaunch Aperture. It should open nag free.
Mac OS X Hints
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