I have created 2 tabs and in layout mode it works fine, then in browse mode it doesn't work properly and sees thru the tab and then you have fields stacked up on top of each other. Please help, I only have this problem in only one of my layouts.
Chances are that the upper boundary of your tab control touches or crosses the boundary line between the body and the header. If you move the control down until this is no longer the case (this can be a move as small as one pixel in some cases.), you should see that this problem has been solved.