Hello, Sorry about that... We tried something but Google just won't let us make updates without breaking anything it seems.
So here is a tuto to keep your save files before updating:
So to make sure you keep you save file, You'll have to manually backup it.
To do that, you'll have to use a file explorer, and find your saves in /Android/data/com.GrizzlyGamer.RMAWhellcum
Copy everything that's in there and paste it somewhere else, In your download folder for exemple.
Uninstall the game, and install the update.
Now you can copy all the files you backuped earlier, and copy them in the save folder: /Android/data/com.GrizzlyGamer.RMAWhellcum