1991 Starlet audio problem

hi, i am new to cars, please help.

PHOTOS: http://www.jasontam.com/stuff/car/car.html

I was trying to install the radio (i thought it would be as easy as install hardwares on computers...). it worked alright, but then the headlights and odometer illumination just won't go. then i detached all the cables, still, headlight won't go. and, don't know how and why, i broke the dimmer...

Hope the photos would help. Please advise me what color of cable should go with what color of cable.

And, what's that brown cable with a red cap?

Thanks a lot!