If you can see the SmartDocs tab in the Microsoft® Word ribbon, but most of the features are disabled, then the document is not able to support the SmartDocs functionality. Usually, this is due to the document being in Compatibility Mode to support Word 97-2003 functionality. A document can be in this mode, even if it has been saved to the new file format (*.docx).
To see if your document is in Compatibility Mode, check whether [Compatibility Mode] appears in the Microsoft Word application title bar, example below:
If [Compatibility Mode] appears in the title bar see the article titled How can I use Older Versions of Microsoft Word with SmartDocs, in the FAQ section, to convert your document to the proper file format.