About the request "22. Include a turn counter in Treasure Hunt", I'd have a proposal.
Since the developers don't like to insert new words inside the game interface, because they have to be translated, simply use 2 turn counters, instead of the single countdown we have now.
After every turn, the left number increases once.
if it's a 4 gems turn, the right number increases once.
if it's a 5 gems turn, the right number increases twice.
When the left and right number are equal, the game ends.
The game starts as "0 / MaxTurnAllowed" if you want to keep the actual behaviour, or "1 / MaxTurnAllowed+1" if you think the zero based start value is unclear.
If you want, the left number can turn yellow when there are only 3 turns left, and red when there is only 1 turn left.
It's self explanatory, and easy to understand.