Thank you very much, for this piece of software (Key Remapper).
I am a left handed mouse user, this was the only software that I found that was been able to successfully swap my mouse buttons.
The great advantage, is that whenever one tries to swap the mouse buttons through the Control Panel in Microsoft Windows, some games, since they have the mouse button configuration programmed in a hard-coded way, will not have the buttons switched has pretended.
This software solved my problems, and now I have, my buttons switched for every application.
I am very happy.
Francisco Castanho, Portugal