OK, I'm probably doing something really stupid here, but... After having my iTunes library hosed a couple of times when iCM was first launched, yesterday I decided to give iCM another try after following the guidance here: https://support.apple.com/en-gb/HT204964 and this time when I enabled it on my Mac it didn't destroy my library. It then took about an hour uploading my more "unusual" tracks to iCloud, and once that had finished I enabled iCM on my iPhone, iPad and PC. However, the only music showing up on those is my iTMS purchases - about 100 songs out of the couple of thousand in my library. I've left it overnight to see if they magically appeared, but it's still the same this morning. I've checked the tracks in my library on my Mac (Get Info>File>iCloud Status = Apple Music) which suggests that my iCloud library has properly been created, but why can't I see it on any of my devices? Someone please tell me there's a simple setting I've overlooked somewhere along the line.