Simple EA Modification MT4 (new lot size calculation)

Hi,

I have an EA labeled  "DayBreaker_FX_EA_v7_16_01_2_bt1.mq4" that has separated "risk input parameters" for buy and sell orders:

"Risk Percent of depo Buy"
and

"Risk Percent of depo Sell"

Now I want to change the EA's logic for calculating the investment sizes (lots). The new formula should be

Investment size (lots) = RiskPercentOfDepoBuy/Sell x AccountBalance x LeverageDenominator* x CR** / 100.000

*  If e.g. leverage = 1:200 then "LeverageDenominator" = 200
** CR = conversion rate between the MT4 account currency and the base currency of the traded pair.

Example 1:
Account Currency = EUR
Account Balance = 2000
Account Leverage = 1:200
Risk Percent Of Depo Buy/Sell = 50 [%]
Traded Pair: EURUSD
=> Lot Size = 50% x 2.000 x 200 x 1 / 100.000 = 2.00

Example 2:
Account Currency = EUR
Account Balance = 2000
Account Leverage = 1:200
Risk Percent Of Depo Buy/Sell = 50 [%]
Traded Pair: GBPUSD
=> Lot Size = 50% x 2.000 x 200 x 0.76518 / 100.000 = 1.53

[because 1 EUR is only 0.76518 GBP, so I must buy/sell less GBPUSD than EURUSD with it]

Who can do this quick and accurately?