We would like to be able to download PDFs or other files via FTP from a web URL which is generated dynamically within Omniscope, just like the current dynamic web links, for example:
If your Omniscope configuration includes a Link definition (see Settings > Links > Add Web link) which you've tested builds the links correctly using your fields, you can then use "File > Export > Linked files" to download the files to a folder.
You can't currently do this in DataManager. If you could it would probably be an output, with the input being a dataset containing your links to download. But this doesn't really fit with regular use of DataManager for managing flows of data.