This is what I use, someone on the forum posted it because I needed it. It will auto scroll up or down just by hovering over the scroll bar in Firefox, perfect for me since I hate clicking, thought I would share it with you, hope it helps:
http://www.autohotkey.com/forum/viewtopic.php?p=285065&highlight=#285065
Code:
#Persistent
#NoEnv
SetBatchLines,-1
SetTimer,CheckScroll
Return
CheckScroll:
MouseGetPos,,,,control
If loop
Return
loop=1
Loop {
MouseGetPos,,,,control
If control!=MozillaWindowClass4
break
MouseGetPos, ax,ay
Sleep, 50
MouseGetPos,bx,by
Send % (ay<by ? "{WheelDown " : "{WheelUp ") . round(Abs(ay-by)/(GetKeyState("Shift","P") ? 10 : 1)) . "}"
}
loop=
SetTimer,CheckScroll
Return