As Chris indicated, the keyboard modifiers let you simulate buttons 2 or 3.  The remaining issue is the chording combinations, selecting with 1 and then clicking 2 (cut) or 3 (paste), or having some copied text and using 2-1 to execute with args.  The patch I mentioned helps with those, letting you sweep left and right to cut, paste, or execute with args.

From the man page diff:

3-finger-swipe left to cut (cmd+x),
3-finger-swipe right to paste (cmd+v),
3-finger-swipe up to copy (cmd+c),
3-finger-swipe down to exec with arg (2-1 chord),
3-finger-tap to middle-click.