Thank you very much for your answer, I was hoping for slightly better news! Even without WRS I was paying all the taxes and was registered for NI number - clearly I was not trying to dodge the system. From your experience, can I still successfully apply for naturalisation having provided contracts, payslips etc?
Also, is failure to register under WRS an actual offence? If so, how serious? I have had several CRB checks, including enhanced checks, and it has never emerged as a problem - can it potentially affect my criminal record? Why have I never been asked about WRS by anyone?