how many coins should I keep on the wallet in order to have the POS?

Good evening I have a problem.
On my Wallet desktop I activated the coin control function since I m using POS ... and wanted to merge all the transactions into one transaction. The transactions were too many (40 for abount 4000.000.000 coins). And the Wallet went crashing. Now every time I restart it bat the wallet tells me that I've passed the Range of Coins to transfer to myself and it is always in crash. After the crash I did a copy of the folded folder in appdata and I reinstalled the Wallet. I re-inserted all the files in the saved folder but crashed me by the same. Now I'm synchronizing the original Wallet again without inserting the old files. But now if I want to get the coins as I can do it because I'm afraid every time I insert the old files it crashes again because the old transaction is running.