late fee calculator

[shakir1401]

hi friends,
i am creating a late fee calculator for which rules are as follows.
1.late fee will be calculated @Rs2/day but maximum fine for a month will be Rs. 50/month
2. month of august will have 2 and month relaxation and september will have 1 month relaxation.
3.session will start from august and will end in july.
4.no fine can be calculated after current month
5.fine will also not be calculated for the months for which fee has been already deposited.
6. the total amount must be in the multiple of 5 rounding in a manner such that 2 and 4 will be 0 and 6 and 8 will be 5.
although i have achieved this but i had to create many columns which looks to be ridiculous.
plz help me to convert this into a smarter worksheet.
the excel file is attached for your convenience to understad the rules.