I gather that the parts (and perhaps score also) of Coleridge-Taylor's violin concerto were lost on the Titanic, on their way to a planned premiere (which of course did not take place then) in the USA. ... is the version that's been performed and recorded a reconstruction from a violin/piano score, or was the lost version not the only authentic full score-or-parts ?
Apparently it was definitely not the Titanic: that was an apocryphal story. But apparently the orchestral parts of the concerto were lost, which meant the composer had to rewrite them. According to the new Jeffrey Green biography "C-T had mailed parcels of the violin concerto's orchestral parts to Stoekel, but they were never received. There has been a belief that the music was on the Titanic, but the Royal College of Music holds the prosaic evidence of Post Office responses to Coleridge-Taylor's enquiries, indicating that the two packages passed through Liverpool and not Southampton. The loss of these pages meant that Coleridge-Taylor was busy rewriting the work as the summer approached". Not entirely clear whether that answers your question.
The full score as it stands is entirely Coleridge-Taylor's own work. After Maud Powell's performance at the Norfolk Festival on 4 June 1912 (using the hastily re-written parts) SCT made some revisions to the score in anticipation of Arthur Catterell's performance at the Proms on 8 October that year -- a performance which SCT did not live to witness, sadly.
Ah! Thanks all.