Sorry sundance,

I edited the previous post while you were replying.

priceOpen(0) is the opening price in this example of the bar from 5UTC to 6UTC i.e the price at 5am and priceClose(0) is the price at 6UTC.

See my edited post for questions on whether this changes when executing trade management functions at tick level in the newly forming bar - you would need priceClose() to give you the price of the last tick and priceOpen() to give the price from 6UTC and not 5UTC.