Is there a way to insert a 2nd "sound" line in the timeline for background music and fx? In the past I attached a 2nd sound to a tree or generic item but if I want to go back to delete or change the sound I don't always remember which item I attached it to and get very frustrated. Should I just wait and add the 2nd background sound when I import it to my video program?
Thank you.

Audio in iclone is and should be used for reference purposes. All your audio should be done in a DAW or failing that in a video editor. Iclone is not for audio work due to its very limited capabilities