Ok, I think it was just a resolution problem. This is probably because your phone is unable to resize the images- anyway, I resized them and updated it in v1.3. I think if you continue playing, you'll also encounter errors regarding 'bg nightlake' and 'bg cloudycastle' (this is because they're not resized in the old version).
I am so sorry for the bug. If you want a smoother experience, you can play it on your laptop. And thank you so much for taking the time to report this bug.