International Trading

At the top of the trade ticket change "Stock" to "International" then suffix the ticker with :IT (e.g. AVIO would be AVIO:IT ). You can choose settlement in USD or EUR -- selecting USD enables automatic currency conversion during order fulfillment.

SG and AU: 

The estimated order value and the commission fee at the bottom use the familiar dollar symbol ($) but it's actually quoting SGD for both. You'll see the US dollar value on the trade preview screen.

Procedure is identical for anything Australian but with suffix :AU and the same dollar confusion applies.