I remember him as an incredibly strong player in the 1980s and 1990s, before he had a stroke. I once saw him get to a king, bishop and knight ending against a fellow IM and Colin polished it off with impeccable technique in about twenty seconds flat! The stroke affected his eyesight (though I don't think he was completely blind) and he was never among the top tier of British players after that.
Oh that's sad. I've actually played in a very low league cup competition against a junior side with Colin on board one (i was deposed from playing him unfortunately, but we won the match on the lower boards..went on to win the cup as it happens..)
He was very active and generous with his time, especially with the children. Pinner juniors will never be the same again, i'm sure in the future he will be remembered for his contribution to chess. Rest in Peace to lovely man.