inventor doesn't show me anything

[meacmae]

I'll explain. I have a 300 mb .stp file if I open it with acad it works, if I open it in proe it works if you open it in the original iventor 2019 it puts a lot creates the tree with all the names of the assemblies, and subassiemi, it creates all the files but I don't even see one individually subassiemi. all files with 56k size but invisible (I attach one). What's wrong?

 

[reb_bl]

the attached axieme is an empty iam idem for the piece, put so you struggle to understand.
How does the step matter? wire? surfaces? compound?
You have a lot of options, how are they set?