Woah! It is harder than I imagined! I'm sorry to tell you I have tried to fix that, but i needed to stop because i must go to work now...
Anyway I saw your project is in 1920x1080 but it is for mobile. You should set it to 540x960 for some reasons:
-Smartphone screens have high dpi values and that lets you create small images with an unexpected HD effect
-Handling too many big images could lead to low performance
-You greatly reduce Download size
I suggest to use 480x800 because if you scale it in "scale outer" mode it will fit any screen out there.
*Tomorrow I'll retry to fix those rings in case you 'll still need help