To delete your OS X wallet qt and reinstall you will need to do this:

1. open a new Finder window
2. press shift+command+g to trigger the 'Go to Folder..' command. Or select it from the Go menu item.
3. paste this into the text field and select Go: /Users/YOURMACUSERNAME/Library/Application Support
4. you should now see your Application Support folder in the Finder window
5. navigate to the folder called 'cleanwatercoin'
6. delete everything EXCEPT the file called wallet.dat (backup this file to be safe)
7. download, install and run the CleanwaterCoin-Qt as usual, and you should be good to go