Arduino Set up

I have reached the position in throttle build where I get totally confused, that is the wiring / arduino set up. I have tried to follow Karls guide to the arduino card joystick set up but keep getting error messages whilst running the Arduino IDE.

Really looking for anyone that can give advice to a arduino dummy in very basic terms. It would be a real shame to have built this wonderful throttle unit to just use it as a desk ornament 😀😪

Any help really appreciated

cheers

Steve