Large brazier falls through solid floor when hauled down

[Steveleeb 1,067]

This may be difficult to explain..
the pottery opening seen in this image has 4 large braziers upon it.
it did have 5 (one covering the opening) until i hauled it down.

unfortunately when i hauled it down, it skipped the solid floor beneath the opening and dropped straight down;

I can't have a ladder visible in the bottom image but it seems the only way to complete the design. 
So i hope for a fix or plantable brazier bowls  
I hope i explained it well enough, ty