Hi Nick,
Clearly this should not happen. Even if you did bump the vest, bits should not fall off it—sorry for that. If you send me your address, I’ll have some new screws shipped out to you.
That joint with the circular plate is there so you can confirm the vest to the shape of your shoulder girdle. There’s an explanation of how to do that in the manual, and there’s a video on my website, link below. Once the vest is the right shape for your body, and the shoulder latch closes easily, all 8 screws holding the shoulder section should be tightened and sealed with Loctite 222.
if you’ve any further questions, I’ll be happy to arrange a video call with you. Please contact me at chris@steadivision.com
Here’s a link to the Exovest videos The one you’re looking for is Sizing the Exovest You’ll find other videos about working with the vest there too
http://steadivision.com/info/tips/index.html
All the best,
Chris