Np.

I have been petitioned by people that I explained how I multi-box to and they were in turn told by GMs that I am not doing anything against the ToS. I am using AHK as well. I've never even been contacted by a GM.

So I am pretty sure you won't get into trouble.

Have fun. You will really love it when you can hit that critical shield button and don't have to worry about tabbing to the other session to do it.