If you have a had a screen replaced, it more than likely will have developed a leak , it could have been fitted in damp conditions or a bad drop in or could have rust that has pushed the bonding leading to a leak , Take it back to where you had it fitted , they will leak test it for you , a word of warning , the galaxy if i remember correctly has a electric box of tricks under the passenger seat , make sure that stays dry or you may have loads of problems !! If I were testing this I would check the sun roof drain holes , open the roof , get some water in a jug , pour it into the corner and it should flow out of the drainage channels in the bottom of the wing , check both sides, if its blocked it will back up ! easy fix , with a thin peice of wire, as for the screen if its that insist that it comes out under the warranty agreement! as a rule of thumb , if you are a nice customer and flexible to leave it with them , they will sort it for you . Best of Luck !