If you add these lines to your autohotkey script, right clicking in fitaly will generate a south slide.
Modify the Y or other distances as needed for your configuration.
Try it out, and when you decide you can't live with out it, chime up on the forum so Jean and Emmanuel implement it correctly. My implementation can't keep up with rapid right clicks.
>>>Script begins below.
WinGetClass, MouseWCL, ahk_id %MouseWID%
CoordMode, mouse, relative
MouseClickDrag, Left, 0, 0, 0, 30, 0, R,