Is it a case of SRM vs. EBC? The promash program I have uses SRM. There's a multiplier factor here (I believe the EBC #'s should be higher for the same SRM) but I can't remember what it is.
I just started using promash, and my first all promash formula has turned out to be exactly what it was supposed to be colour wise. I made a 1.1% addition of Carafa Special for an ordinary Bitter which has turned out quite tasty.
You should post your question here, as the program's designer checks the boards regularly and is quick with answers:
If all else fails, trust your gut, as it is a beer gut afterall.