I also used Adjustments in Render menu, along with Colourize brush to adjust the colours to my liking. Also, I activated a pink coloured fog for my render. Zbrush is an ultra fast renderer, so this was actually rendered real time.
Step 10:
Back to 2D painting. I used the Smudge, Paintbrush and Highlighter brush to paint over my rendering. I also used the Glow and Intensity brush for the artificial lights.
Here you can see the close-up comparison between the rendered and the painted images.
