For what it's worth, I just asked the same question on Reddit, and somebody pointed me to a program called PlayerPro. It will recognize artists and albums successfully, but not playlists. I'm also not sure if I can tell any app to shuffle via google now.
PlayerPro is a paid app, but I might try other media player apps now that I know that different apps work/don't work differently.
For PlayerPro, have you been able to get it to play via Google Now, without having to quit the Program?
I can get GN to recognize my speech and play any of my songs via PlayerPro, however, after asking it to play a song, i have to quit PlayerPro, (not pause, or dismiss) to get it to play any other song i ask for. if i just request without asking, it only opens the player.
To the original poster: Try asking GN to "Play" instead of "Listen". You may have a difficult accent or pitch, Try to rephrase the command. GN seems to recognize a number of ways to get what you want done. And if that fails, Rename your album to include a second or third word, so that GN doesn't confuse the song, and the album.
I reccomend you get this PlayerPro program, they have a free trial. it's great. It will allow you to rename, your files, and albums. try it.