I've just taken the plundge and purchased the full version of GT Shadow: $697.
I'm more and more convinced by the logic of grid trading and see it as an investment strategy rather than a trading system. So yes there will be long periods of drawdown as the currency trends away from its centre towards its high or low value.
Drawdown will increase exponentially as this happens but will eventually reach a theoretical maximum. Profits however, though linear, have no limit and will eventually exceed drawdown over time: it is absolutely inveitable as long as the account keeps trading.
I hope to make around 5% per month on a $7500 live account trading just the EURCHF pair. I prefer this to the AUSNZD because the spread is much less, so more profit for me less for the broker.
Ill keep you informed how I get on, but it will be a long slow process!
Regarding the currency shadowing feature, I had this nice reply from Forex Goldmine:
"The Shadowing feature is actually the hardest one to explain, 
it's a feature that allows you to hedge trade different currency's,
while you decide the different midpoints of those currency's, through
a shadow profit, which is a hypothetical profit, so instead of
calculating the midpoint by a number of pips, you are calculating it,
through a profit, that you would accumulate if you would of started
trading at a certain point, this is a great feature to use if you are
hedging two different currency pairs at the same time.
We are working on a in depth tutorial that will explain that feature,
to your fullest understanding, which should be available very soon."
I think this is a great EA with huge potential and much more flexiblity than Robominer, thats why I've spent a lot of money to get it.
Wish me good luck.