Signing Certificate Problems

Background: I have currently 4 apps in the MAS. I have successfully signed all of them using App Wrapper.
The Problem: Everytime I go to sign a new app, it seems there are problems to be encountered. In order to create an installer for the MAS, I select Developer ID Installer in App Wrapper. It reports that the certificate is invalid. I go to Keychain. I select the Developer ID Installer certificate. Keychain reports the certificate is valid and gives a little green dot.
Attempts to Resolve: Sam suggested uninstalling the certificates from keychain and reinstalling them. I select the certificate in Keychain, press the Delete key. A popup asks if I really want to delete this key, I respond “Delete”. Nothing happens. I right-click on the certificate and select “Delete”. The same dialog appears. I select “Delete”. Nothing happens. I have gone to the Apple Developer Connection and downloaded the certificates, but, apparently because they are still in the keychain, clicking on the newly downloaded cert. does nothing. I have tried to follow the instructions in XCode Help, but they differ considerably from what I actually see within XCode and Keychain.
I have an app ready to go to MAS review. Any suggestions as to how to solve this much appreciated.

Roger, I apologize as it seems that I made a mistake yesterday. The certificate you want for sending to Apple is not a Developer ID certificate. You want the “App Store” identity, it may appears as either “App Store”, “3rd Party Mac Developer Application: Roger Clary” or “Mac App Developer: Roger Clary”.

If you don’t see any of those, please use the “Codesigning Diagnostics” from the “App Wrapper” menu and e-mail me the results.

I am also running into a similar situation. @Sam Rowlands , I just sent you the Codesigning Diagnostics to see if you can make anything of this

Found the solution. See the following posts. After deleting the expired Apple Worldwide Developer Relations Intermediate Certificate, the certificates in Xcode show as Valid and not Revoked. And also in App Wrapper, the App Store identity is now present.