22seven is incredible. I realise you want to keep it very simple, requiring as little user intervention as possible. However, there are some things that can enhance the program for the user.
Starting balances. As 22seven shows the closing balance it may as well show the opening balance at 1st March. This way the categorising of (transfer) transactions between accounts can be correctly done. Income and expense accounts start with no balances but the all the linked bank, bond or investment accounts do. It may simply be entered by the user if it is not picked up automatically.
Loans and refunds etc. As there seems to be no real distinction between Income and Expenses except for the fact that the figure is negative or positive the categories keeps them separate. This applies when you loan someone money and they repay it in parts or in full or when you buy something and there is a part or full refund. It would be useful to enable the linking of two or more transactions to show a balance or net figure. The improvement will be that the refund does not show as an income. I understand that if this happens across two months it becomes problematic. Maybe there is a way.
Thanks for a great idea. I hope you go from strength to strength.