Thanks Orson, Mathprofrockstar... and everyone else.
Yes, Floor pronounced the Scottish (and northern England and who knows where else) way is completely valid, it's not an exotic sub-species!
I suppose I had a similar reaction (as in 'no, floor/flaw is the correct one') when a Times crossword gave Earn and Urn as soundalikes. I was quite indignant, until I read the pronunciation notes in Chambers.