[Solved] Ivory question mark on my object

Hi guys, I just made Air Conditioner with simple box mesh, but I have a problem.


I could load my Air Conditioner in The Sims4, but got big ivory question marks on the object.


 




I wanted my object just for DECO and not functional, so my base file was knight sculpture.
(from Base game)





This is my work flow... Please read and find out what's the problem. 

1. First, I opened blender, appended Air Conditioner mesh and transferred weight. (the knight sculpture has weight so I transferred)
    replaced my mesh and saved blender file.
2. Imported my Air Conditioner mesh and texture to Sims4studio, and I didn't wanted the shadow meshes, so I deleted shadow LODs in Warehouse.
3. Saved and load the CC in the game, and discovered question marks on my CC.

The one thing I am concerning about is... the size of Air Conditioner texture is different from the knight's texture size.

Knight Sculpture -> 256x512
Air Conditioner -> 1024x1024

Does it matter if there's differences between the texture sizes when making new mesh objects?

I wish someone could answer my questions.
Sorry for my poor English.