VOSA put out new advice on (among other things) airbag lights. "The requirement for an SRS warning light to illuminate has been removed". I do not know if the requirement that originally fitted equipment must be present has changed - I guess it hasn't.
Plus advice that the particle filter on a Diesel (sometimes referred to as the CAT) does not fall under the test for the presence of a catalytic converter. It must still pass emissions tests.
Full FIA harnesses will now pass too.
Full advice sheet here:
http://www.dft.gov.uk/vosa/repository/Special%20Notice%203-12.pdf