There were a lot of bloopers in this one, and they all seem to be Catherine related.
1. When Vantann and Kip arrive, and they go int to the warehouse, Catherine isn't wearing her holster. But once they are inside, she has it.
2. When Nick is moving Vartann, in one shot, Cath is holding Lou's jacket, in the next she's not, then again she has it.
3. When Nick and Cath are talking at the hospital, Catherine's scrape on the side of her face seems to have magically disappeared from 10 seconds before. I'm guessing that they filmed the hospital stuff over two days, and didn't bother doing the makeup because they figured they could film from Marg's left.
I'm horrible at catching bloopers, and I've seen three so far. Seems like lazy editing to me.