Thanks for the speedy replies.
We remembered the +2 bonus vs downed foes but not the auto-kill. OK. I'll make a big note.
Yes, we did Follow Up to Recoils, as well as the mod for Outnumbered, but the more I reflect on last night, the weirder it seems. There were toe-to-toe brawls everywhere, but the dice were consistently rolling low. Opponents would get knocked down, only to stand up and keep slugging away turn after turn. There were constant 2+ failure turnovers, endless 'not quite double' combat scores, a bunch of tied scores/no result, incessant reaction failures, just bleah....
We're going to label it a Bad Dice Night and keep going, but man, it was strange.