hi jac,so i will tell you what you can do...
FIRST: you have to remove side trims...be very careful because they have a very thin lugs and you can brake them very easy.
SECOND: you have to remove the sun visors and the center lapm( just pull it down,it's easy)
THIRD: Remove the front left and the front right panels ( for the hand).Just unskrew
this should be enough to pull down just a litlle bit down the back side of the roof and to see if the drains are not in the proper place.
It's not so dificult as it seems
try it