Snuffy, from your post, Forest Green must be the melody that V-W used. The reference I had just said "English melody."
The Radner version in the Cyber Hymnal is the one commonly heard in the USA and Canada but the V-W is also sung by choral groups. I don't believe that I have heard the Burnap tune except on the Cyber Hymnal midi.
The Cyber Hymnal mentions Walford-Davies as a composer of oratorios and choral suites but doesn't cite him as a tunesmith for "O Little Town..." They do include 3 hymns for which he wrote music.