Xcode 4 places its build products and other intermediaries/temporary files/indexes in a derived data directory now instead of a "build" directory that is mixed in with your product files. It does this to deal with the new workspaces and also so that you can have clean builds of different projects in different workspaces without contaminating each other.
If your original template was old, your built product is probably relative to your source directory instead of relative to your built products directory, which is why it's showing up red. By default, your derived data directory will be under ~/Library/Developer/Xcode/DerivedData. To see where your current workspace/project is placing these files, you can File->Workspace Settings... and take a look at the Build Location.
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