I think you can open the final enclosing folder if you just edit the path to remove the file name. In the above example, that would be using OpenURL with this path:
file:///C:/Users/Me/Desktop/FileMaker Pro 13 Advanced/External documents/Section 1/
It's fairly easy to use the position function to get the postion of the last "/" in order to strip off the file name.
Of course i can open the folder containing the file, but this folder can contain thousand of files, so not so easy to retrieve the file !
That's why i need to just select the file (without opening it), like i do on macOS with the "reveal" applescript function.
On particular on Windows, having thousands of files in the same folder isn't the best idea from a performance perspective. You could perhaps adding a new subfolder level (with a name based on a record id, date, or whatever), to reduce the number of files in the folder you would open. That's of course not exactly the same as Reveal, but could help anyway.
The MBS plugin has a function http://www.mbsplugins.eu/FilesRevealFile.shtml. I'm guessing you should be able to achieve the same without a plugin, maybe using vbs.
Word of warning: Externally stored container assets should never be touched through the OS. They should be excluded from backups, and should never be shared out for user access. Why? Because doing so involves a high risk of damaging the links between the database and the assets, rendering them irretrievable from the database.
You can point to it if you want, but never touch it.
Ideally, just create a script that uses the "Export Field Contents" script step to export a fresh copy of the file into the Get (TemporaryPath) folder or the Get(DocumentsPath) folder or the Get(DesktopPath) folder. Also, check the box that says "Automatically Open" to open the file after export.
That way, your original external linked copy of the file remains safe.
You can also prompt yourself for the folder path that you want to export a copy of the file to by using the "Get Directory" script step.
However, if you really do want to open up the original file, you would need to use some sort of a Windows OS command and send a command to the operating system Itself. I don't personally know how to do that on Windows, so I would personally just use the Troi File plug-in to accomplish this. You could also use the 24u SimpleFile plug-in to do this as well.
Many Thanks David.
This plug-in works fine !