It seems my output window has stopped appearing when compiling. I have seen similar problems in other versions that have been resolved by deleting a key in the registry. I have not seen any issues reported or resolved in IS2012 Spring though.
I don't believe significant changes have been made in this area, so I would probably go with the registry deletion (with appropriate backup) as a first try.
HKCU\Software\InstallShield\\Professional\IDE\Workspaces contains automatically saved settings that could negatively impact layouts including the output window.
