System unable to verify software after download

Question

I think this was covered in earlier discussion threads, but I don't see that it was resolved...  Maybe I missed it.
Problem: OS X Lion successfully downloaded from app store onto my 2009 iMac running OS X 10.6.8, but took 16 hours. My DSL is normally pretty good and quick, and I turned everything else that was connected to it off before starting the download, so that was surprise #1.
Lion icon moves to the dock when the download started.
Tried to install by clicking on the Lion installer icon.  Got the installation screen.  It started working and told me 3 minutes.  1 minute later (after signingin and agreeing to the SLA) got the error message "System could not verify the software.  Possibly corrupted during the download."  I clicked on that error message and the installer disappeared.  Finally located it in the Applications folder.  Surprise #2.
I figured a download problem, possibly a permissions problem (had recent minor trouble with Firefox crashing frequently.)  I fixed permissions using Disk Utility.  Then re-initaited the App Store download.  16 hours later (I'm going crazy here), the exact same scenario occured.  Starts to install, then stops and disappears into the Applications folder.
Wrote App Store tech support, who recommended right clicking the installer and opening another .dmg that is allegedly in the download package.  One of the stranger things I've ever heard (Surprise #3), but I check any way.  Right clicking or control clicking the installer icon does absolutely nothing, nor does opening the installer app from the Applications folder.  I'm not seeing this dmg anywhere.  No download package that I see on this machine.
I advise the AppStore folks of that, and they basically throw their hands up in the air.  Paraphasing here:  "Nope, don't know what's happening, if you'd like, I can refer you to someone else."  They were very nice about it, but geezzz. So much for putting any effort into the problem.
Checked these forums, found earlier threads from last July that seemed to say the issue was in memory handling.  The recommended solution seemed to be going into the Terminal and making some changes.  Also found a link to a cnet blog, but again, not happy or comfortable with attempting the suggested fix.  I have a very, very low comfort level with doing that, so...
Also the earlier threads seem to have linked this problem to MacBook Pros.  I'm running an iMac and having this issue, so it's not just a portable device problem.
Getting tired of surprises here.
My questions are:
Has anyone found a solution that does not require personally making changes at the terminal level?
Does anyone know if Apple has ever officially addressed this issue?  I've been searching and can't seem to locate any knowledge base article that addresses this specific problem.
thanks to all for your patience with a long-winded question.  I promise the next one will be limited to 140 characters.

Answer 1

Control-click the install app and select Show Package Contents. Open it up and the dmg that should work, given an uncorrupted download, is the one marked. If you can't get to that, then the download app is useless and you'll have to waste another 16 hours downloading a good version. Alternatively, visit an Apple Store and let them get you a viable copy, since Apple loves this new, but lousy, delivery system.