Adding songs without rescanning everything?

[On1]

Hi Team, I'm new to UAPP and need your help.

1. In picking up the music from ITunes, using SyncTunes, so I'm assumming UAPP is taking info from that, am I correct?

2. How can the music be missing in UAPP and available on another player.

3. Can you edit the song/album etc in UAPP

Thanks,