There's m,any theories as to what the seven rooms symbolize but here are two popular ones. The rooms symbolize the seven stages of life from birth to death or that the rooms symbolize the seven levels of Hell. Take your pick, you can probably argue better for the first one, though. Each color has significance to the stage of life it represents, I can't remember all the different colors, but you get the idea.
In the revising stage you should edit and reread the memo to make sure that thats what you wanna say
