A transition of that length is very unlikely. .500 would be a half-second. Switch to Storyboard mode to see if there is an unwanted, short clip between those intended for the transition. Delete it.
As for the "overlay" ... are you referring to the area that states: Drag clip here to add to end of sequence?" If so, cClick the double-headed arrow icon near the bottom-right of the VP screen to fit the entire project into the timeline. Or scroll it with the nearby slider.