I have added 2 buttons - one will change all the values in column F to Zero (0) and the other button will update the balances as per your instructions. Let me know if needs any changes. I have attached a workbook for you to try. Remember that when you run VBA that you cannot undo the changes so make sure it works to your specifications and perhaps do a backup before running on real data.
PS: You say in the workbook Button 1 should clear all Movements to zero however in your post you said Button 1 should reduce Balances to zero. I followed the instructions in your workbook. In your post you refer to CP's in column B - I am not sure what you wanted with this?