actually, just tried it some more, and found one issue
if you move your cursor to the edge of the screen (or window if playing windowed), the game starts its usual edge-scrolling! so if for example you want to scroll to the right, you "grab" something on the right-hand side of the screen and "drag" to the left, but once you reach the edge it starts scrolling to the left, because you hit the left edge!
I think there are two possible fixes for this:
1) disable the edge-scrolling mechanism while holding right mouse button (scrolling should continue beyond the edges of the screen, then.)
2)
invert the edge-scrolling mechanism while "battleScrollButton: [whatever]" is pressed AND "battleScrollButtonInvertMode" is "inverted"
btw, I think you should change that "battleScrollButtonInvertMode" to accept "true" and "false" as options, to have it consistent with the other "switches" in the config file, don't you think? maybe call it "battleScrollButtonModeInverted" instead, defaulting to "false".