Dear CATIA community,

I have a question regarding CGR file format.

I successfully imported a CGR file into CATIA 3DExperience using the "Import CATIA File" feature, and I can view the part with the CGR viewer (see picture below). 
 

Here are my problems: 

1) I cannot see the tree structure (just a part in that case)

2) I can't use the part in an assembly design. 

3) I do not manage to convert it into a solid.

So I'm asking the community 😛  Does anyone have a clue on how I can convert this into a solid I can use in an assembly?

I really appreciate any help you can provide!

Maxime