Thanks for the quick response. In response to the troubleshooting:

1) I just went into the game and attempted adjusting all the graphical settings while observing the fog texture glitch (the easiest and most consistent one to observe). At every graphical resolution, from the lowest to the highest, the problem remained the same. I also switched between the preset graphics settings offered, and then went and manually lowered all the settings to their lowest degree, to similar lack of effect.

2) Just checked, and there is no software update available.

3) A clean boot also failed to change any of the problems.

It's possible that this is related to the problem listed on the store page, but the symptoms are different: the store page says that action icons may disappear, but that has never happened to me (except as part of the entire HUD disappearing). And the store page doesn't mention anything about glitched character model or fog textures.

It's possible that this is a problem I'll just have to resign myself to, but I wanted to at least try to see if there were any other options -- and possibly to get word passed along to the Mac development team, if it's a bug they might need to address.