Complex Bonus Calculation

Hi Excel Gurus.

I have a bonus calculation problem. Unfortunately I was not able to solve it by myself. Uploaded sample file and explained all the details there. In short to explain:

My bonus spreadsheet have to calculate bonuses that has been paid. I do not consider only sales but payment from customers is important. But date of teh sale and payment is not the same and in calculation of the bonuses I have to take account percentage which sales hase been made. Also payment can be about previous sales' payment and advance payment, too.

It better to take a look to the file.

Thank you in advance.

I made a mistake there in 7th month bonus calculation. It have to be 40 not 30. Others are correct. Sorry for that

Any ideal pleaseş

explain in detail if possible....we can't have clear understanding what to do.....!

Every detail has been explained in sample sheet (second one). Calculations are simple but make it true in excel is difficult. Waiting for any kind of idea. Thanx

Any idea?