In the help file / manual, you indicate that Extended Properties are visible in the Metadata Pane, and that DO will use "an ADS stream" to store the comment (https://www.gpsoft.com.au/help/opus11/index.html#!Documents/Extended_Properties.htm "Comment: Specify a comment for the file. If the file format supports a comment field natively (and Opus supports metadata for that file format), then the comment will be stored in the file itself. If not, Opus will use an ADS stream to store the comment. You can also choose to use the descript.ion comments system - this lets you save comments for all file systems, but results in an additional data file being placed in the same folder. See the File Descriptions page for more information about file comments."), so I tried with filenamepath:Comment, filenamepath:Comments, filenamepath:Tags and filenamepath:Someother in order to write, programmatically, Tags into a .txt file's different (see the names above) ADS streams, and I also read those values correctly, programmatically.
Unfortunately, in DO's metadata pane, those values do not appear, nor do the respective ADS (ie the names of the streams).
Conversely, possible values I enter in "Extended Properties" "Comment" and "Tags" fields, are not visible in the ADS "Comment", "Comments" or "Tags" or elsewhere, but are scrambled into binary format within the ADS "ENQSummaryInformation" and "{4c8...d}".
Can you tell me if there is any other text-only format (plain-text which I can read from, and possibly also write to, programmatically), and which (name and value, in case) would appear within the Metadata pane of DO?
If there is currently no such plain-text ADS (of any name) that DO can process, can you give some code I could apply in order to process the values of "Comment" and/or of "Tags" within DO, programmatically? (I need a script to access/change those values, and do not know currently how I could do this, considering the values appearing in DO are unfortunately stored in binary format by DO.)
EDIT
The "programmatic setting of Metadata" does not seem to work for me since I need access from outside of DO, within a more general script, and which also contains "if value/string is / contains... then ...", in other words, I must be able to read the current content, then work upon the result of this "seek". (I have seen the help page "Keywords for SetAttr META", and have seen that even a tag replace can possibly not be done by +x;-y since +x does not check for the existence of y first it seems, so that x is always added, even if there is no y to be deleted. Let alone more complicated checks/conditions.)