How do you change wall color on both sides of a corner?

[Jpl68]

Also, can you drag wall colors from one area to another? Doesn't seem like it but thought I would ask. On the corner issue, I can only seem to change the color on one side?

[Unregistered]

The shorter wall has a shadow so the same colour will look darker. I don't think you can move sections of wallpaper, but you can put other colours on top of them and the original should go into storage 

[GummyBear07]

About your quesiton for the corner wall chaging all you have to do is put it in the corner then wiggle it after you click once then click again and it should be on the other side of the corner