As d12 said, Twilight can use SketchUp's sun. It's just that I did the first test with the sun turned off and a completely white sky for a moody, monochrome look.
Twilight has several render presets available. Some of them work similar to Indigo/Maxwell/Fry and are called "unbiased"; others work similar to V-ray/Mental Ray and are called "biased".
For the first test I used an unbiased preset, Easy 09. For the following one I used a biased one. I also turned off the light for a change, and enabled the physical sky + sun with some tweaks to their default values. Lastly, I did some post-production in the freeware app Motiva RealCamera, trying to simulate an Agfacolor camera. π
Agfacolor-HDC200plus.jpg
UPDATE: I'm cooking another one with Easy 09, wait for it...