I'm making progress, guys, I've got the detailed sketch of the characters! I still need to adjust some proportions and the final position of a couple of things. I already chose the time of day for the picture, it will be in the evening. Because I want to draw nice lights, I think it will be very atmospheric this way. ^^
This picture has helped me a lot so far on how to use the perspective ruler in CSP. Such a fantastic tool!