Riddles;
Blue: What is as big as you and yet weighs nothing.
Green: What do poor people have, rich people need, yet if you eat it, you die.
Red: What begins and has no ends, what is the ending of all that begins
Yellow: If you've got me, you want to share me, if you share me, you haven't got me, what am i?

On green side a sign spawns and if you knife it you get a message "Blue Zone: Destroy the rock with a rocket launcher, upon shooting the rocks on blue side, a perk soda power-up spawns under the center platform. Note: shooting the rock without knifing the message does not yield the same power up.

On Yellow Side is a box that will turn power on for the platform allowing you to get around. Note: After i turned power on to the platform zombies all immediately became runners causing some difficulty.

Please post any additional information you might have, I intend to do the same if I can ever make more progress. Actual progress seems to be difficult due to a bug causing the game to crash while loading.