Drag and Drop just isn't it.
The idea was ok, so were the graphics. Some people actually like drag and drop games like dressing games.
But the execution wasn't good. I mean, you can place stuff on the wall? and in the middle of the grid?
You should have done some extra research about grids or tiles and used them for the game, just like in Habbo.
After you've done that, you need something to make the game interesting. It can be music. It can be extra features like saving a picture of the room. It can even be an option to submit that picture to a database to share it with other players.
It's just clearly not it.