Thanks for the link. One vehicle class I was unable to find was NQIW. It may be that I was not careful enough but if they are missing from the list can anyone advise what happened to these.
NQIWs don't exist nor have they since the National Rail days in the early/mid 1990s when they became RQIWs. They were a two TEU container flat whose original intent was as a never built coal hopper.
The wagons, whilst theoretically great (light weight, low deck, high speed, high load capacity), had Gloucester bogies which were unsatisfactory due to a dished centreplate design which caused/failed to correct wagon list. I think that this problem was ultimately rectified by modifying CCSB capacity (constant contact side bearer).