$ ./kobaltw assemble                                                                                   ~/t/MaterialAudiobookPlayer
            _  __          _               _   _
           | |/ /   ___   | |__     __ _  | | | |_
           | ' /   / _ \  | '_ \   / _` | | | | __|
           | . \  | (_) | | |_) | | (_| | | | | |_
           |_|\_\  \___/  |_.__/   \__,_| |_|  \__|  0.503

/var/folders/77/kjr_lq4x5tj5ymxdfvxs6c7c002p8z/T/kobalt8232969414796676742.kt:92:13: warning: variable 'leakCanaryVersion' is never used
        val leakCanaryVersion = "1.4-beta1"
            ^
          ╔══════════════════════════════════╗
          ║ Building MaterialAudiobookPlayer ║
          ╚══════════════════════════════════╝
───── MaterialAudiobookPlayer:clean
───── MaterialAudiobookPlayer:generateR

Here is what I get with my copy (which you just merged into yours)