So, just updated to Android Studio 1.4 Beta 4 and having trouble building a release build. I can build a debug build fine. This is the error I get:
ExternalS
I had the same problem but with this error:
ExternalSystemException: String index out of range: -119
My problem was that in the string editor i forgot to set a default variable into my translation, after adding it, the problem was solved.
Hope it helps!
If you're using Android Studio, selecting the Gradle Console will show you where the problem lies. In my case, it was duplicate textView identifiers that caused this error.