Your stove probably has an "Empty" fill with a backgound screen colour pen (-1) set.
Your table and chairs may not have an empty fill or it may not be set as "Empty" fill and/or the background pen colour is wrong (0 instead of -1).
Slabs have always been transparent but you do have an option for a cover fill - use either a solid fill with a white hatch pen or an empty fill with a screen colour background pen (-1).
You may still have to play with the display order - the slab will by default go behind any objects (ie the tiles).
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11