My driver's seatbelt got stuck in the up position - would not pull out or wind in further. After a struggle I managed to remove the trim panel on the centre (B) pillar - you need to prise the panel above and below before it comes out. Peel the door rubbers back to get your fingers / flat chisel under the plastic. No screws on the 2007 facelift.

Once I got my fingers on the seat belt reel, I was able to wind the belt a tiny bit and the obstuction moved and the belt freed.
Had a cuppa to celebrate !!