Hi, all. My Itunes library has been a mess since iOS 8.4, but things seemed to be looking up when I subscribed to Apple Music a couple months ago. So I thought I'd give adding songs from my own music collection another shot. I have never done this on the mac before. I hooked up my external hard drive that contains a massive folder of music files, opened iTunes, pressed command o, picked the external drive in the sidebar, navigated over and interacted to select the music folder, opened that with command down arrow, interacted, navigated to a folder that contains completed albums, pressed command down arrow to open it, and it took off adding all the files in that folder. It had added several before I could stop it, and then I had to go through and delete the ones I didn't want. I tried again with the same result. How do I get any further in the folder structure so I can select what I want to add?