I know how hard it is.
What you have to do is make a wall named "unit" or even the floor and then a wall will be attached to the floor pattern you put in. So you go to the build menu and put up a unit wall or unit floor. But most importantly DON'T make the units where the outline of you land is. In other words where the grey tile ends, SHOULD NOT be where your patterned floor ends. Make it one square less.
Hope this helps.

thanks! ^_^ I'll try it!

it wont work

I tryed it but all it does is make everythinng enclosed. ? What should i do ?

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