Can't uninstall games with "Delete local content"

Solution 1:

Try redownloading Steam. If that does not work, there is a directory where most of the Portal 2 game files are located. Navigate to:

~/Library/Application Support/Steam/SteamApps/common/portal 2/

Then, delete the "portal 2" inside /common/, the whole folder, not "portal2" in the "portal 2" folder.

One warning here, OS X 10.7 and above hide the Library folder in your Home (user) folder. This is different from Libraries and different from Library in the top level of your drive. To permanently show the Library folder, use Terminal:

chflags nohidden ~/Library/

Alternatively, one may hold option while in the Go menu and click on Library, or use the Go To... command in Go and type ~/Library/. This is only temporary.