If you have a margin click which occurs at the left-most pixel location of a margin, I don't think the notify code will fire. For example, if margin 0 is clicked with the X location equal to "0", then it won't be recognized in the following code:
bool Editor::NotifyMarginClick(Point pt, bool shift, bool ctrl, bool alt) {
int marginClicked = -1;
int x = 0;
for (int margin = 0; margin < ViewStyle::margins; margin++) {
if ((pt.x > x) && (pt.x < x + vs.ms[margin].width))
Shouldn't the first equality check be ">=" (ie "pt.x >= x")?
-John