If it helps I can share my ideas and solutions to problems. My leg knife strap keeps slipping, so I've put snaps in the back of my leg fabric to snap to the strap behind in a way the strap hides it. I also placed one to snap on the front directly to the resin knife. We drilled into the resin, used chicago screws with plastic weld to set them firmly. So far, I don't have anything out of place anymore.
As for the chest armor, I'm going to have to shorten my plates next week. I'll have to post how I do that then, as I really don't know where I'll stick snaps at, but yes you do use snaps on the back of the armor onto the vest. Though I'm fairly sure the CRL says to put a fastening to the cummerbund. Honestly, I think you ought to place it where it moves the most. Hope that makes sense.
Thumbs up for the Spanish Garrison for the Zam Armor Party! :love That's some love for ya, Mirval!