You're supposed to install it through the D loop on the shoulder strap, but when I did that, it seemed to put a little extra pressure on the shoulder strap. Not a big deal for the short term, but I could see it being a problem on a longer hike. I ended up hooking mine through the handle on the back of the pack, as I don't think you can reasonably draw your bow off a fully loaded pack, without tearing up your rotator cuff.
Try attaching it on the highest row of the padlock system, and make sure weave it on pretty tight. If you attach it lower, it will angle out away from you, causing the bow to tip out.
I have one and never explored it before hunting. Had a hard time figuring it out so I didn't use it. I have a Matthews Z-7 with horizontal limbs and it isn't a great fit, but could be done. Like to fall out if not just right. I will have it down for this fall. My buddy found it was a lot of fun to slip rocks into the bucket while we were hiking in, and listen to me complain about why my pack seemed so heavy. He got his monies worth out of it. He has told the story a hundred times.
Until this thread, I never realized that the Dragonfly and Just One only had a couple of rows of the PALS webbing. I've got the Blue Widow and it has twice as many rows... Sounds like the idea of having additional rows sewn on might be the ticket. Perhaps you could query Eberlestock and see if they could do it for you?