In order to view your account values displayed in a currency other than their native currency, you will need to set up currency exchange rates. This is accomplised using the Price Editor.
Open the Price Editor by going to Tools -> Price Editor. Click on the Add button to add a new currency exchange. A window will appear to allow you to select the commodity you wish to define the exchange rate for. Click on Select and set the Type to ISO4217 and the Currency/security to EUR (Euro). This window should appear like this:
Click Ok and in the Select Commodity window, set the exchange rate between the selected commodity and the selected currency. In this example, we will set the exchange rate to 1 EUR to 1 USD.