In a previous post it was mentioned to me that when playing a 2-3 Zone I should be be taking advantage of this and shoot more 3's. Is the only way to do this to increase the +1 or +2 settings for individual players? The highest I normally have the 3 point frequency is 0, what is the difference between +1 and +2 when dealing with frequency? 

I don't want to blow the game by jacking up three pointers the entire game, but I want to avoid what happened to me when I was beat by a SIM AI team that I was favored over by 40.

I would never use +2 that is just asking for trouble. Basically the guy will jack shots up that any right minded person wouldn't shoot (that's an exaggeration but you get my point)

At first glance, it's not that your guards aren't taking a high enough percentage of their shots from behind the arc against teams playing 2-3 zone, it's that your post players have largely dominated the distribution in these situations. Take a look at both the Delaware Valley and York (PA) box scores.  

As nachopuzzle said, basically you should just increase the distro for your 3pt shooters when you play zone teams. That way, they get more shot opportunities but don't just jack up ill-advised 3 pointers all game long

to make it easy to adjust your distro as suggested, here is what i do - I allocate my distro with a goal of having a total of about 80 - then when I want to increase the distro for a guy or guys, I can just add a bit to them - if I want to cut I just cut

at one point I tried to allocate based on 100 and adjusting was a lot more hassle

technically, you can have any total you want - distro is about the ratio between the numbers shown, so you can make them add up to 20 or 80 or 100 or whatever.  Around 80 feels good for me and makes adjusting easy