An ajax currency conversion widget to let your visitors convert currency amounts on the fly (powered by Google Finance).
Check your currency lists have data in them in the WP Currency Converter settings page found at Settings -> WP Currency Converter.
Make sure you use the three letter currency acronym as per the ISO 4217 standard
This plugin uses Google Finance for it's calculations so ensure the currency is one they support.
You can add any currency by it's currency acronym as long as it's in the ISO 4217 standard list.
It's likely that you're not using a currency code that Google Finance recognises. To check you can try Googling for the currency conversion, eg. 25 AUD to USD (replace with your currency codes).