Here are the steps needed to add a ‘Dicom’ block:
- In the post editor, find and add a ‘Dicom’ block,
 - Click the 
Media Librarybutton, - Upload files on the 
Upload Filestab or choose some from theMedia Librarytab, - Click ‘Select’,
 - This brings you back to the editor and adds the dcm shortcode to the post,
 - Click the 
Previewbutton to see it in action! 
You can click back on the generated shortcode to make the ‘Dicom’ block reappear and modify your selection.