For Best and consistent results while choosing the effects choose all the three.Running the application with the provided video and mp3 should take about 2-4 mins and a dialog is displayed upon completion .In case at the End the video does not automatically play, the created file can be viewed manually at the location of the video file, with the name custom2.mkv. This application produces AC3 audio format which most players support. Try a different video player in case there is no audio. Utilize the apk from app/build/outputs/apk/apk-debug.apk in case final.apk fails to install.