There is no tag or shortcode or anything like that that is <file titles> or anything similar. That bit of text only exists in the little bit of help text underneath setting #11 in the EBD settings. It’s just trying to tell you that if you don’t put anything in #11 then it will default to the message “Requested URL for the file(s): ” followed by a list of the files. In other words, the <file titles> thing is just telling you that’s where a list of files is going to appear in the subject line. Again, there is no tag like that that you can use.
If you want a list of files to appear then you have to use [files] as the tag. So you might put something like “Here are the files you requested: [files]” in setting #11 and then that [files] will get changed to the filenames. I looked through the code and it looks to me like it should work. I couldn’t find any bugs that would cause the [files] to not work in the subject line (setting #11) but work in the body. However, I haven’t tried it, so it’s possible that it’s just a bug .. but, again, looks to me like it should work.
In order to test it, I think you should make up an entirely new message to put in #11, just for testing purposes. Don’t use anything you’ve used before. Maybe something like:
Here are some files bro: [files]
and then test it and make sure that the email you get as that first part “Here are some files bro:” in there …. maybe somehow it’s not registering your change or something.