then I'm pretty sure they upload into iTunes as a single CD.
Your problem is probably in the way you are viewing your tracks.
Try changing the view to Albums instead of tracks and you will find that Slashs 2010 solo CD appears as one CD with multiple guest artists
For example, I recently purchased Slashs 2010 solo CD that has a different guest artist for vocals on all 13 songs. Instead of uploading it as 1 CD with 13 songs, it uploads it as 13 seperate songs and no artwork. I have many CDs that are compilations of artists and its the same issue with all of them. Anyone find a resolution yet?