Ok, the xls did open and I could look into it. However, your calculations appear too complicated - there is no need for this many parameters. I think you only really need three:

Must_Remain = Capital * sqrt(1 + Profits/Capital)

Available = Capital + Profits - Withdrawals - Must_Remain

Trade_Size = some_factor * (Must_Remain - Withdrawals)

Capital is the initial capital at the first start of the system, Profits and Withdrawals are accumulated since the first start.