LEDs designed to plug into an incandescent bulb socket won't give you the look you want. (Which I assume is the look of recent Cadillacs, Infinitis etc). These cars use an array of LEDs that fill the entire lens. A single LED in a bulb socket will look anemic since it won't relfect off the back of the assembly like the incandescent bulb it replaces.
Colored bulbs behind a colored lens make no sense since you're just decreasing the light output of the system further. If the lens is red, a red bulb behind it will just look dimmer.
Colored corners behind cleared out lenses would work, if that's the look you're going for. Though, it's not really in keeping with the looks of the Murano IMO.
True Xenon HID bulbs and ballasts, while theoretically possible, would be a problem for lights that are intermittently used (brakes, turn signals) since these bulbs are not designed to flash. You could, I suppose, wire them up in the brake lights and parking lights. This would require some fabrication to make work.