Trying to get Gamecube controller w/ Mayflash adapter set up

So I have this adapter and a Gamecube controller and while it functions, I mean I can play games and all the buttons work, I have 2 things I'm trying to get sorted out:

1) The L/R analog and buttons. In the Windows devices area for the controller, it properly shows the analog area of the buttons being an axis, and also it has separate button assignments for the "clicks" when you go all the way down on the button. But in Dolphin, I'm not able to set the analog area as one command and the button click as "Button 5," or whatever. It just shows the axis for both. Is there any way to get it to show the axis for analog and the button for the click?

2) More importantly, the sensitivity of the left analog stick. I mean I'm able to play games and get through them, but for something like F-Zero GX, it really stands out and I feel like I could be doing better than I am if the analog stick was setup better. Does anyone have any solid recommendations for what I should use on all of the analog stick settings in the configuration? Range, threshold, dead zone, etc? Anything on this would be greatly appreciated.