Actually I found a workaround. The issue likely came from JoiPlay corrupting images. So here's what I do: put a random image in that save folder and rename it "save3.jpeg". The image will then show the that picture instead of screenshot; but at least it don't break.Doe anyone else got this problem?
Due to some problem, I needed to use JoiPlay to run the Win version.
I initially used the Android one, but it has a bug when I try to open the shop and basically shows similar "Can't find. Retry." Message. This issue isn't on the Android version.
However, this is a 1-time fix. If you save again, you will see the problem again. Unfortunate, since you will need to replace it again and reboot JoiPlay each save. I think this is an issue of JoiPlay. Is the save picture command means the game take a screenshot and use it as a picture for the save slot? Because if so, simply removing the command to put image in there will fix JoiPlay players.
Anyway, here's hoping for a fix for the Android version shop, which the author has (I just read) stated that it is a known issue. If I may add, though, please allow long tap om Amdroid to function as skip, because the skip button is in the middle of the screen and it is hard to reach.