Seems to work fine over here. Your sprites pack into an atlas with the size of 1024x2048, but my default behaviour mode remains as 3D. The scene view is set to 2D though. What size is your final atlas texture after creating the atlas? Maybe your quality settings are set to fastest, limiting it to 1024x1024?
By the way, I would strongly advise you to reconsider your sprites. PLAY and REPLAY buttons in particular... text should be just that -- text (labels), and their background can be done using a very small sliced sprite. Same with a few other sprites you have in there.