QUESTION White windows with banner

[QuestoDK]

I have a problem where i try to make a window banner for a car, but when i try to add the graphic to the car in Content Manager, the windows get white and non transparent, and the banner is faded. I use PS to edit and save as BC3 and have tried different sorts of configs in it but all the same. Is there a way to fix this issue so that i can add stickers and banners to my car?.