Yes there are some issues on certain versions. Even the unmodded game still crashing on Android 6.0 and 7.0 since 4.0.0 release. The dev f**ked the compatibility
I know but you see the issue only comes in the Modded app, it is as if the game has some kind of mechanism to detect any changes in the game( i.e. modding) and then kinda freeze the game after one battle in FW, making the player to restart the game.
Its just my theory but you know better, and maybe you can do something about it and fool this mechanism !