The next time I experience this problem, I will certainly try desktop resolution and colors! I had gotten past the situation with the snow trolls I'd found so far, by the time I got your idea.
If I have another opportunity to web / entangle trolls and I get stuck again, I certainly will try it out.
My workaround was to change tactics (which is why I was disatisfied with the workarounds condescendingly alluded to above, because those weren't solutions, but workarounds I had found on my own already).
As I said, the game became a lot more tedious, but perhaps I should have taken more chances
Though I don't like reloads because of deaths; kind of kills the immersion...