I never quite understand what is meant by dollar terms or yen terms.....unless you have stacks of all currencies and have to decide which one to spend on gold, or when selecting a currency to lighten up to. Is it more complicated than that, like going short a currency as well?

It's exactly like that. Go long gold and short Yen in equal dollar amounts. That's essentially the Yen/Gold cross, and means you've gone long Gold in Yen terms. Lather, rinse, repeat for the Euro, Sterling, etc.