No plus or minus button in Xcode localization settings

Solution 1:

It moved to the starting in Xcode 4.4 .

Solution 2:

I just meet with this problem and I was using xcode 4.5 preview 3. Couldn't believe apple have made this kind of mistakes and not fixed it even when its at preview 3. Therefore I believe they just have changed the way localisation work so I poke around the UI until I finally found it.

They have shifted it. You first have to add the language you want to the project first. Then after it will appear as a check box item in the UI you show. To add the language you need to click go to Project -> Info then click "+" to add new localizations.

Hopes that helps.