Let me introduce powerful method to solve a puzzle.
It is the "reductio ad absurdum", which is used in the field of mathematics. This method sometimes leads you to solve a difficulty.
"A simple example 1"
There are floor panels which belong to another room and a blank cell in between.
Let us prove that the item of the cell in which a white circle exists is a block.
(1) Assume that the item in the cell is a floor panel.
(2) Two different rooms are connected. But that is absurd - it contradicts the rules of the game.
(3) So we can conclude that the original proposition must be true. Thus the item must be a block.
"A simple example 2"
There are three blocks connected each other in an L-shape.
Let us prove that the item of the cell in which a white circle exists is a floor panel.
(1) Assume that the item in the cell is a block.
(2) A big square is made from four blocks. But that is absurd - it contradicts the rules of the game.
(3) So we can conclude that the original proposition must be true. Thus the item must be a floor panel.
There is a numbered floor panel( "6" in this figure) where another floor panels surround.
Let us prove that the item of the cell in which a white circle exists is a floor panel.
(1) Assume that the item in the cell is a block.
(2) Connecting floor panels maximum makes a 4 floor panel room. But the area could not reach to 6. It contradicts the rules of the game.
(3) So we can conclude that the original proposition must be true. Thus the item must be a floor panel.
(2)' Connecting floor panels maximum makes a 5 floor panel room. But the area could not reach to 6. It contradicts the rules of the game.
(2)'' Connecting floor panels maximum makes a 3 floor panel room. But the area could not reach to 6. It contradicts the rules of the game.
(3) Three floor panels are fixed.
"Generalization of the method"
You have to fill every cell with an item, either a block or a floor panel.
If you guess an item of a cell is a floor panel, assume that the item is a block and find what will happen.
If it contradicts the rule of the game, you can conclude that the cell should be filled with a floor panel.
Similarly, if you guess the item is a block, assume that the item is a floor panel.
However, if no contradiction is found, what is meant by that? It means that environmental conditions has not been prepared yet. In other words, it is too early to determine the item of that cell.
Please leave it untouched for the time being and investigate another cell.
This method is all-purpose and powerful. Try this one when you have come to a dead end.