Hi I eventually fixed the airbag light after going out and buying my own renault clip. The problem is allmost allways caused by a dodgy connector on the seat belt pretensioners the 'official' fix being to cut the two wires to each pretensioner at the plug socket and solder them insulating with a bit of heat shring. (it takes longer to remove replace the seats) but has worked a treat with my own and another half dozen cars i've fixed.
I think I'll be going down that route too. Thanks for the top tip!