I am getting an error like this:
[WARN]Warning: Multiple build commands for output file /Developer/B/Be/build/Release-iphonesimulator/BB.app/no.png
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This happens if you have 2 files with the same name in the project. Even though files are in groups in XCode when the project is compiled all of the files end up in the same directory. In other words if you have /group1/image.jpg and /group2/image.jpg the compiled project will only have one of the two image.jpg files.