Who is the author?
MYBB or a specific staff member? If so url to profile?
Justin designed the 1.8 theme and I'm pretty sure he designed the 1.6 theme too. It might have been Chris who initially designed it but with the amount of commits through out our repo it's hard to say for sure.
The 1.6 theme is actually the 1.4 theme really. No major changes have been made in many years.