I have purchased an app which didn't download successfully. I deleted the installer and tried to install it again from the Mac AppStore but the download button says "Installed".
I also still have the app icon in my Launch Pad with the download progress indicator on it.
I'm aware of the option + click on the "Installed" button and on the Purchases button, but neither works.
How can I reset this download process to enable me to download the app again?