It seems that from TS 09.02 version 4.2.0 on, the editors have actually put markers as "hidden text" inside the Word document, which allow better automatic detection when a given ASN.1 module starts, is interrupted by plain text, continues and ends. The following screen shot (from Section 14 of the above-mentioned document) is human-readable hidden text explaining the syntax:
So now I'm adding this format as a second option to my extraction tool.
Please note: The tool I wrote yesterday (working fine with version 3.x.y of 09.02) is available from asn1_docextract.git. Later today it should also support the >= 4.2.0 annotations outlined in this blog post.