Well, sorry for trying to help. I told you to refer to the tutorial because you asked why the Draft folder couldn’t hold non-text files, and this is explained thoroughly in both the tutorial and documentation. To say, “It’s not a law of the universe, but a design decision” is like saying that not allowing you to edit Excel files in Photoshop is a design decision of Photoshop - true enough, but meaningless. It is a design decision, yes; and one that has a very good reason behind it, one that should be clear if you have gone through the tutorial and understood the whole purpose of the Draft folder, which is why I pointed you in that direction. I wasn’t telling you to RTFM, but rather pointing you to materials that would answer your question more thoroughly.
Yes, this is the technical support forum, and people are trying to give you technical support - both Ioa and I have tried to help you. But it’s difficult (and not entirely fun) to give someone help when they come back with spiky, overly-critical answers rather than describe what is happening in detail. What is happening (or not) might seem simple enough to you, but as many details as you can provide are always helpful in zeroing in on the problem.
All that aside, if something in the Draft folder is selected, a PDF added to the project via Save PDF to Scrivener should get added to the Research folder regardless - it shouldn’t fail.
I said this isn’t a bug because I’m confident it’s not a bug - I’m confident about this because of how the PDF services work (if I’m wrong I’ll eat my hat and give you a refund). There may be an issue with it right now on your particular system owing to the way PDF services use aliases and are prone to flakiness, but I’m 99.999% sure it’s not a Scrivener bug; thus we need to find out what is causing the problem on your system. Hence the questions…
I asked which application you were trying this from because although it is indeed a system dialogue and shouldn’t matter, it would help me try the same thing from the same program. I just tested it out with Firefox and it worked fine, though. To be clear of my steps, I went to File > Print… in Filefox, selected “PDF” in the bottom-left of the print panel, and chose “Save PDF to Scrivener”. There’s no other way I know of doing this, so I assume this is exactly what you are trying.
The “Save PDF to Scrivener” feature is a system-defined thing, too. An alias in the PDF Services directory sends the PDF file to Scrivener, so it seems as though it is failing to send the PDF for some reason.
If you haven’t already, try double-checking that you don’t have Scrivener 1.x still installed anywhere. Although the path is pointing towards Scrivener in the Applications folder, it’s not impossible that it’s getting re-routed to a copy of Scrivener somewhere else.
Also try moving the “Save PDF to Scrivener” alias from the PDF Services folder to the Trash and emptying the Trash, then relaunch Scrivener. This will cause Scrivener to recreate it.