How do I tap on bottom right to trigger a secondary click?
What you need is BetterTouchTool. I use it to define actions for taps in corners of my trackpad, but it knows abut middle of top and bottom of trackpad. It can do taps, swipes and gestures with up to 5 fingers. It is so configurable that what it does is only limited by your imagination or your ability to remember what you have configured.
This was also the answer to Triple finger tap for middle click.