2CO Payment currency convertion

Hi

I am using KWD currency in my site

2CO doesn't support my KWD currency

the problem is :
when someone buys something that's 19 KWD
when he arrives to the 2CO payment page he'll be asked to pay only $19



I want 2CO to convert the KWD to USD based ON MY RATE so that my customer is asked to pay $62

i contacted 2CO and they told me this is an issue to be solved within my store script.

How to solve this problem

Same issue for my store my local currency are BHD but it's not supported by 2CO.

Please someone assist us to resolve this issue.