the taskbar is no label. if you've hooked the taskbar on a label. you can do very easy, just create a non visable label above the taskbar (maybe hooked) and give it the events.
the problem is, that a taskbar above the label surely doesn't react on mouse events, cause there issn't a label.
also, if you want to hide the label with all hooked modules, just hide the label, you don't really need a custom script for that, all modules on the label will be hidden/moving too