Songs can be ineligible if they are too low quality (96kbps and below is not allowed in IML.) or if the individual track is 200mb or more in size.
I can guarantee you that the songs that caused problems for me were nowhere near those extreme cases, they were just plain, standard music files, some even some fairly recent purchases from the iTunes Store. And extrapolating from that, I would say that the vast majority of songs other people have problems with also aren't those extreme edge cases.
#2 (cloud with an "X" in it) could be that in his frustration he unknowingly removed some songs from IML from his phone or even the Mac. The Mac will still see them in the library because it's local on the Mac. (Thus no longer in IML) Once removed you need to re add it.
I think that should never happen in the first place, when I delete or 'remove' a song, it should be deleted, possibly with a warning if it is song that is 'owned' compared to one that is 'rented'. Already now one can differentiate between deleting just the locally stored download of a song and removing it from 'My Music'. Only if you wanted to have an option to unclutter the view on an iOS device by not only removing the download but also the listing, would it make sense to have a 'remove from My Music' not causing the song to be also removed from the iTunes library. But you can unclutter the view already now by limiting it to only locally stored songs. An integrated cloud-based, synced to all devices music library shouldn't mean that deleting a song in one place has to be followed up with deleting the song in other places.
Before iCML, iOS devices generally contained what iTunes put on them. Yes, you could buy songs or movies and they would transfer back to iTunes (I think) but those were exceptions from the rule (and rented movies already weren't part of that). But I always thought iTunes wasn't totally clear whether deleting something on a device (be it a song, an app or a movie) would stay 'deleted' after syncing with iTunes (it didn't always, sometime iTunes put things back on, keeping the general notion alive that an iOS device contained a subsection of an iTunes library, controlled by iTunes.
#3 (dotted cloud) could be he added some songs AFTER IML did its initial scan and/or uploading of his library when first turned on. (Thus not in IML yet and needs to be added)
Again, I think that should never happen. Why would for example purchasing a song in iTunes (or ripping a CD) not add that song to 'My Music'/iCML? Isn't spending money on a song a very clear affirmative that I want that song to by part of my music?
So you would rather just complain and give up than actually try to solve it?
Believe me, I spend about 20 hours in total trying to solve things (not only this problem but many others with AM/iCML). At some point you have to call it quits and accept that the sensible decision is to wait a while for a good deal of the bugs being fixed.
Seems lazy. It's pretty cut and dry really. You had songs NOT in IML. Find which ones, add them back. [/QUOTE]
After you have added the same song three or four times, this feels like a futile enterprise. See above, I am not giving up on iCML, I am passing the baton to other fellow beta-testers and let them help Apple to fix most of the bugs and once that is done I'am coming back. I don't think there is anything lazy in (sometimes) skipping 1.0 releases.