Thanks - I've changed it back. There's a dropped kerb along with a bike symbol painted on the cycleway near the Masterton R/about which, along with lack of blue cycle/pedestrian signs on that stretch, plus the narrow pavement, suggested to me that it was not a cycleway. I have consulted the Fife Council adopted roads map, which says it's a cycleway, so I've changed it back.

It could be argued that an unsigned pavement of a width not designed to be a shared footway is not really a cycleway, but I'm not particularly convinced by that argument in this case.

I don't see any signs in the Bing image you posted. If you mean NCN signs, they don't necessarily indicate that the NCN route is on the footway - it could be on the carriageway. And whether something is an NCN route doesn't really have anything to do with whether the footway has been designated as a shared cycleway by the road authority.