First off... You didnt say what kind of game it is. There could be numerous things that cause that. Maybe too many Periodic triggers that run every second or so. Too many units that are created or killed in that time period(turret wars, lag would steadily get worse and worse as the game ran on, because of how many towers were placed, and how often things would happen) So... whats your map about... check for repetitive triggers, or actions that occur in the game... does it always freeze at the same exact spot? Time your game, and see whats happening at that time.. It might be when a player does something, so that time may be different. Try to get a closed group of things that cause it. Then ask your question again... | 
