Hi Franco,
Which version of Xerte are you using?
Which version of Moodle are you using?
If I understand you correctly you are uploading an exported Scorm Package to Moodle.
Which version of Scorm did you export your course to?
From your screenshot it appears that the index of your course did not import correctly.
Adding more information to your post may help you get an answer quicker.
Would you be willing to share an example of an export you're having trouble with. I'd be happy to check if I have the same issue when importing it into our Moodle Dev environment.