Mind the spread! For a pending buy test against
double a = MarketInfo(symbol, MODE_ASK);
and your pending-buy must be > a+minimal difference!
Play around with different prices to become acquainted with your system!
Thank you so much.
I finally figured it out. It had nothing to do with spread or the 'obvious' things we've been looking at.
Instead, the order type e.g. OP_BUYSTOP was not been interpreted correctly into its numeric figure in OrderSend.
That fixed the issue.