Thank you !! It's worked ! :D But now i have another problem: When i have the good number of Coins to buy the upgrade (The Coin with a cursor on it) and i click on Shop to go to the shop layer, the game automaticly do the buy of the upgrade, without i click on the sprite. Here's a screen from the code (i have added a line but i don't think it's that)
PPS= Pièce Par Secondes (Coins Per Seconds in English)
PPC= Pièce Par Click (Coins Per Click in English)
PCP= Prix Curseur (en) Pièce (Price Cursor (made of) Coins in English)
The others valors aren't important (I think).