With Xcode 5\'s new Asset Library, adding images and organizing them has never been easier. However, it seems as if it has broken some scripts I use for creating builds.
If your plist file is Preprocessed-Info.plist, then change the value of "Preprocess Info.plist File" (INFOPLIST_PREPROCESS) to "Yes" (true) like this:
Preprocessed-Info.plist
INFOPLIST_PREPROCESS
true