Create a new autohotkey script, then right click it & edit the script. Paste the following 3 lines at the bottom and save. Then double click on the file.
Code: Select all
#IfWinActive ahk_class XmainClass XButton1::PostMessage, 0x111, 335, 0, , XnView XButton2::PostMessage, 0x111, 336, 0, , XnView
That is all. Please let me know if this helps you.
You can download autohotkey from http://www.autohotkey.com/download/ - the first link for autohotkey_L is fine.