Thank you for taking the time to write about your experience. I am sorry to hear about the issue you encountered trying to play my game. Going forward I will bugtest my projects on a wider selection of devices and OS systems.
-There are a total of 20 levels.
-Levels are cleared by reaching the flagpole(Endpoint). This was included in the tutorial however, considering the instructions are not "immediately readable" you must have missed it.
-Additional music is no bother at all.