Hi Nicccc
Sorry to see that no one has replied to you yet. AccountRight is not specifically designed to track GST collected or paid in other countries and as such will not give you the option to choose a different currency when setting up the tax codes.
Here is our article explaining how the multicurrency feature works: What can and can't be done with multicurrency in AccountRight.
Hope that helps, but otherwise you might want to check with your accounting adviser to determine the best workaround for your circumstance.
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