It ain't made by webasto, firstly. The pop out roof is the genuine article and has 4 drain holes (1 at each corner), each drain hole has a beige rubber pipe connected to it. The pipes for the two front holes run down into the sills. You can access these two by removing the vinyl boards in the drivers footwell (what the fuse box bolts over), and the one in the passenger footwell (with the speaker holes punched into it for the mono system.
Pull out the ends and blow some compressed air through them (remove sunroof 1st though), it may be nessasery to unclog the ends with little rods if they're clogged up with mud.
Don't yank them though!!! If you pull them off the end of the drain holes you'll have to remove the roof lining to put them back on!!!
The rear hoses are behind the boot side wall panels which means, a ball ache to get to. Seat belts out, parcel shelf shoulders out. The good news it that only the fronts get clogged, the backs are rarely the problem.
You can try blowing compressed air through the actual drain holes 1st though, see if you can clear it the easy way 1st. Then pour hot soapy water down each hole, give it a good flush.
Alternatively you could buy the lady a hat
