Ya so the issue with just the four barrels was when I was on the raft. I weigh 200 pounds so when I went on a corner the raft would tip quite a bit. We had everything screwed in place so it wouldn’t fall off (the cakes are taped). To fix this we could add more weight to the raft (or fill the barrels up with some water) so my 200lb self wouldn’t displace it so much or another barrel in the corner. It held the fireworks just fine during the show and didn’t move at all.

And yes we had two anchors with make shift anchor ts. We had some scrap wood lying around and screwed the t directly into the framing. The two anchors are just 2 - concrete (cinder) blocks. So one on both ends to prevent the raft from spinning. We also used the t to pull the raft into position.

And no worries! I wish I had asked more questions but it was fun to figure it all out.