May I ask about the ceiling of Bimobject ?

[LeeJaeYoung]

1. Can I create a zone like this?

2. What should I do with the perforated area?

1~2 I found that it was possible without holes.

[Kevin Lee]

my 2 cents with ceiling

1. Just use slab with ceiling texture. In many cases, you won't need all the ceiling details(tracks, veiling to slab connections, separate panels) in 3D. 

2. If you do need detailed 3D representation, try using the curtain wall tool.  With the CW wool, you can control the level of details and representation from MVO too,

[LeeJaeYoung]

Can you show me the image you made with the curtain wall?

[Kevin Lee]

see the example below.

FYI, you can use the "boundary" option to draw it from the floor plan and even use the magic wand over the room boundary.

[LeeJaeYoung]

thank you so much.
I will study hard.

[David Gulbrandsen]

It is in norwegian, but you might understand by the cursor and menu options clicked.. 

https://youtu.be/aRVSCTqilYE