hhhmmm...I just followed your instructions, exactly, three times and nothing happened. When you clear the puzzle and get the relic, do the squares stop lighting up when you step on them? That last "right" that you gave me put me one more square past the empty alcove as well. I wonder if we are talking about two different relic puzzles? I'm pretty sure this was my first time there. It's just an empty brazier like thing in the far alcove with nothing in it. It's in the Desolate Wilds, in the Agyn Peninsula.. It's directly a couple squares to the left and up of the NPC Huang.
Your solution was rather simple, I dunno if it was possible to screw it up, so I'm thinking we are talking about two different relic puzzle areas?
The squares light up this way: yellow means that one adjacent tile has a bomb, orange means that two adjacent tiles have a bomb. I mapped it out on a grid and put x's where there were bombs (ended up reloading my quicksave a lot). There is probably more than one way to reach the other side without dying; I ended up staying mostly on the left of the map. I didn't bother to map the whole room once I got my relic!
If I remember correctly, once you safely get to the alcove on the other end, there's a small, easy-to-miss ornate box on the left. It's not the standard large chest right smack in the center. There's an artifact but I don't remember which one.