I'm installing floor registers in a new built, how close can you put a floor register to a wall? I know the rule of thumb is 4 inches from under your drywall and floor molding, is that the minimum distance or can you move the register in closer? Also, they say to put a floor register in front of my stationary patio door, would this cause condensation on the door or window in the cold months, I have all double pane glass in all the doors and windows. Any help would be appreciated..