1 - I don't trade currencies, but since nobody answered you....
2 - I use 16/20 ma crossover, and RSI (legacy preferred, which TOS has) set to 20 periods, on half hour bars, on the dollar index.
This is just my default setting for something I look at but don't trade. It gives me a reasonable sense of what the trend is.
It's background info to my trades in GDX, the etf for gold stocks. If I actually traded it, I'd probably zoom in a bit more.
As an FYI, the only thing I look at in RSI is whether its above or below 50. I don't think the oversold/overbought lines have any meaning at all.