Had this problem once. You need to download winpac and reprogram your ipac to use different buttons. basically the ipac mimics a keyboard. reprogram it with winmac to use letter keys. leave the arrow keys alone though. They seem to work fine. Also, when you are done with this. Go to startx and in the RetroPie folder go to configs folder, then ALL folder, Open retroarch.cfg using leafpad and scroll down to where it shows keyboard input. Uncomment those lines by taking out the “#”. Also, you can add a second player by copying all those input lines and pasting them below. Then just change player_1 to player_2. delete all the default keyboard keys in the file and use your controller to enter in the keys you want. Hope this helps. and dont make the mistake of thinking you are almost done. I have been feeling that way for a month.