This is a really interesting animation, I love the black & white art style as well as the transition between scenes. Lovely work.

"Its just a prank"

People are still making madness animations in 2019?
but
overall good animation

I'm not sure if this is going to be helpful but.
For the Flash or the Newgrounds Player issue(well, which worked for me)
You go to your time/dates and change the date to the 10th of January 2021 or before 2021.
You refresh your browser and launch the player.
Hope it works for you.

The game is looping with the same platforms, Its not a bad game but some music or sounds would have been good
(also I'm guessing this took time to make with programming but your trying)

An accurate simulation of a cheapest windows 98 or used

Is it me or do I think that this image reminds me of The White Stripes - Seven Nation Army music video?