I'm attempting the mission where you must escape from the Powerplant(?) in the dark. I know the goggles help but unfortunatly sometiems I am killed even before I can use them! There seems to be a big problem here, let me expalin:

There are yellow dots on the tiles which I can see. If a guard is on one of these dots then I can attack him. BUT! Sometimes these yellow dots just seem to vanish for good and I cannot understand why. I can't get passed the guards because they block my way, even if I am stood right next to one and had just been attacking one, sometimes on my next turn the dots just vanish and I can't attack them anymore.

Why is this happening? I've failed this mission numourous times now because of this and it's really irritating

In the beginning Roger saids you will lose sight if you get attacked. I think attacking and then getting countered is the same.