How do you place multiple floortypes in one room?

[Quotex]

Hello,

 

I am currently working on a custom building.

 

I wanted to make a few variants of the Zippee Market, so i decided to explore this building ingame. I noticed that the store interior has a  Grey-tiled floor with a red tile outline. I am trying to do something similar, but i can't seem to figure out how to put more then one floortype in a room.

 

The only way I found how to do this is to make a room that covers the outline of the room and then make the walls invisible. But i suppose this would give problems if you put the building in game.

 

Also, I had to put in the Zippee market textures, as they weren't in the list, is it supposed to be like that? Will the containers be lootable, even though i had to put them in myself?

 

Thanks in advance,

 

Quotex

 

EDIT:

 

I read through the building tutorial by Thuztor and overlooked the tile mode had a tilesets tab. That solved it.