I think the spirit of this request was missed.
I too noticed recently that after hitting insert on a lyric that the insert window didn't close. Now I am not sure if that was a recent chance or if I had just missed the behaviour before, but I would prefer to find a search a song, find the version, confirm the lyrics are correct, apply the appropriate template then click insert and have the song dialog box close.
Or maybe have two buttons, one that just inserts and one that inserts and closes. (That actually seems like a better option).
I am not sure what you mean by playing cue on the fly.