Converting a 3D model in blender into S4S...

Hi, I am totally new to modding. I have only recoloured some hair and objects, but now I want to learn how to convert free 3D models from sketchfab for example. I started with a juice package, using the feng flower vase as a base mesh. My model looks accurate, like a juice package but without texture of course, in blender, but when I try to import the mesh to S4S, the vase is gone but the flowers are still left. What am I doing wrong?

I'm following this tutorial: josiesimblr.tumblr.com/post/173963696459/convert-3d-objects-to-ts4-part-one
josiesimblr.tumblr.com/post/173964874564/convert-3d-objects-to-ts4-part-two