Using group channel tracks - ideas?

I am hoping someone with good mixing experience can give me some advice.
I make add tracks for documentary-style videos. I work with a rough audio track of spoken narration. As I get close to mixing down, I want to bring the whole music track down to hear how it should sound when it is mixed by their production people. I don’t want to bring all the music track faders down.
I have been sending all the music tracks to a group channel track (except for the speaking, of course). This works okay, except I am not able to assign the FX tracks to the Group Channel. It is blocked because it creates a feedback loop.
I wonder if there is a technique or feature that is a more elegant way to approach this situation. What I want is to control the balance with just 2 faders - speaking and music - for the purpose of previewing my mix before I send it out.

Um…why are you getting a feedback loop? I add both aux and insert FX to group channels all the time. where does the feedback loop occur?

A great question- which just helped me find the answer! It didn’t make any sense to me, I was just going by what the manual said about the horizontal line.
When I opened the sends in the mixer, I discovered that Group Channel track had a send to the reverb. I think I must have activated a Preference function that did it automatically. Once I shut it off I was fine. Thanks a lot.