Wow updating the proguard in C:\android-sdk-windows\tools actually worked for 4.15 ! This is amazing! It got rid of the
BUILD FAILED
UATHelper: Packaging (Android (ASTC)): C:\android-sdk-windows\tools\ant\build.xml:871: Can’t read [C:\android-sdk-windows\platforms\android-27\android.jar] (Can’t process class [android/R$xml.class] (Unsupported class version number [52.0] (maximum 51.0, Java 1.7)))
Thanks so much.