Due to the current Project 64 version's input / controller plugin being inaccurate, it is REQUIRED to use this plugin shown in the image below if you wish to play on emulator. Download it from the resources tab above and place it into the Input folder directory where you installed your emulator.

Select Options on the top bar and click Configuration (or Ctrl +T on the emulator). Select plugins, then select Jabo's DirectInput7 1.6 from the drop down menu, click OK. Restart the emulator and your settings will be applied.