Ok, so Xcode 4.1 was working fine and I did the incremental update to 4.1.1 at the App Store when it came out a few days ago. Nothing has been stable since that update.
So I found on Stackoverflow to use the command: sudo /Developer/Library/uninstall-devtools --mode=all in uninstall the environment.
It seemed to work as expected. After that, I deleted the remaining empty subfolders in the /Developer folder, emptied the Trash, and rebooted.
At this point I have in every real sense uninstalled and revoved Xcode 4.1.x. So I go back to the App Store to re-download the full current 4.11 package. Yes, I am on Lion. But the Xcode page in the App Store continues to state that I have the package INSTALLED ! And so, does not provide me the ability to re-download it.
Why will the App Store not permit the re-download of a free product in its entirety, as a registered Apple Developer, even if I did have it installed ? Which I don't.
What to do ? Thank you, I am in a bind here. I need to affect some setting on my Mac that will not indicate a false-positive that I have Xcode installed. Ideas ?