Excellent, thank you, that worked a treat.
I don't understand why it's so hard for things to be done correctly though. I use Media Monkey and have spent a lot of time getting things right, with all the correct album art, it should just work.
I had two problems this thread helped me fix. One was the missing album art (that's there on the PC) which is fixable with the MPAtool and the other was albums being split up, turning off the Xbox music sync fixed that. But we shouldn't have to jump through hoops, if the info is on the PC and we sync, it should stay like that and ASK before it starts splitting albums up. I had only got 5 of my 500+ albums over and two of them were split. These were mainstream run of the mill albums too!
Ah well, hopefully some one will write a better music player for WP8.
Thanks again for the tips.