My 120" Vapex tensioned electric screen was developing like wrinkles in the center near the bottom by the bar. Aggrivated I tried the tension system but no luck, didn't want to snap the lines. So out of random I grab the bottom bar and curled it up slightly like if you were going to roll a newspaper. But only enough where it forms a "U" shape at the bottom. Then I slowly put it back down. No more wrinkles! Thought id share this with you all. Also I noticed if the room is hot the screen has a tendency to have more wrinkles.