How it works is this: If you pick UConn you have to subtract 5.5 points from their score (or add 5.5 to GT's score). So in that case the bet is UConn if you think they win by more than 5.5 points or GT if you think the Jackets will win or you think they will loose by 5 or less. Does that make sense?
Example UConn 82 GT 80 (GT +5.5 wins)
UConn 88 GT 80 (UConn -5.5 wins)
GT 76 UConn 75 (GT +5.5 wins)
The over under is a little simpler. You are betting if the total goes over or under the total of 146. By total that means the total of both teams scores.