The far left arrow is for changing the color palette for the ambient lighting.
The round knob controls the ambient lighting intensity. From off to full on. This will not work during daylight. Try it when it's dark outside.
The far right arrow turns on all the cabin dome lights, provided that's how you have them set up at each individual location above each door.
2013 Ginger Ale Titanium 2.0 AWD, Factory Tow Package, Pano Roof and Roof Rack, Kuga LED Rear Tail Lights, Factory Added NAV, factory Added Rear Camera, Rear Spoiler, Build Date - Sept. 2012