/Apps/QuickLook? I've got absolutely no idea what that may be about.
All else aside, though, just (do as I said in post #32209) create a new folder, name it "QuickLook" (no quotes), place it in ~/Library, and drag the SP plugin from wherever it is now into that folder. You'll wind up with ~/Library/QuickLook/Suspicious Package.qlgenerator, and selecting a .pkg and hitting your space bar will reveal the .pkg's contents.
Edit:
To install, find or create the QuickLook folder inside the Library folder, under your home folder. (On Lion, hold down Option and choose Go ➤ Library to get to your Library folder.) Drag the Suspicious Package icon into the QuickLook folder. You may have to log out and log in again for Quick Look to recognize the plugin.
(If you want Suspicious Package to be available to all users on your computer — and you have administrator privileges — you can copy it to the QuickLook folder inside the top-level Library folder instead.)
