Hmmm, I think I like it. The fruitloop / spectrum progress bar is neat. I can't judge the accuracy of the WPS to the original firmware as I'm not a sansa user, but I assume 'knock-off' means that you are trying to mimic the original firmware as close as possible and not use it as inspiration?
One thing I suggest is doing something about the very loud, top half of the backdrop, the bright turquoise is a bit painful on the eyes, maybe tone it down a shade or two, or add in a gradient. Otherwise, it's a very clean and simple WPS, easy to read so it gets good marks for my taste in WPS's.
Good luck towards the finished work