Please can you replace the feature Open in External Editor with something that provides a range of choices like the Open With contextual menu item in Finder.

I would like to be able to open a PDF in Skim without having to change the default setting for reading PDFs in Finder which I have set to Preview.
Many thanks.
Workaround: You can set things on a per-file basis, as well as the system-wide default. A single PDF file can be set to open in Skim while the rest open in Preview. To do this, open up the Scrivener project package and sort by file type to group all of the PDFs together. Now select them all and press Cmd-Opt-I to open the group file info palette. In the Open With section, choose Skim (but do not click the “Change All” button).
Thanks for the workaround Av… but I can’t keep doing this every time I want to work with a PDF, so I will just wait for v2…
Thinking further, I want to have Preview as my default Mac OSX PDF reader and while Scrivener 2.0 will have some new features like highlighting built into it, I would still like to open an imported PDF in Skim.
Perhaps in addition to an ‘Open in External Editor’ option, an additional setting could be added to Scrivener Preferences to ‘associate’ a specific application to manipulate PDFs when using Scrivener.
Or be done with it and strike a deal with the developer of Skim and build that code into Scrivener…
I’m afraid there are no plans for anything like this in 2.0, although it’s not a bad idea. Maybe in a 2.x release.
All the best,
Keith
P.S. I’m talking about the “Open with” bit, obviously, not building a full Skim-like app into Scrivener, which would be madness. 
I also would like the “Open in External Editor” for PDF files to allow me to specify, in Preferences, the exact PDF editor I want to open. I would like to be able to enter the URL of the .exe file.
The reason is that Adobe overrides my Win 10 default choices where I select Adobe Acrobat 9.5 as my default PDF viewer. Adobe will not permit my system to select that version of Acrobat as my default viewer. It forces the stupid Acrobat Reader DC as the default, instead.
So when I open a pdf file in Scrivener with the “Open External Editor” button with the intent to highlight something or perform OCR and do a word search, or to extract a page, etc., the file opens instead in the Reader, which can do none of those useful things.
Adobe’s commercial motive in this proceeding is transparent, and its interference with my system defaults (as well as its deliberate sabotage of older but perfectly good versions of Photoshop, another story) are obnoxious and probably deserving of litigation. But there it is. And meanwhile I’ve got projects to write. And it would be very helpful if Scrivener would help me to work around Adobe’s manipulations and allow me to specify the pdf editor of my choice.
Thank you.
Well one thing to note is that this was posted in 2009. A few years after that we did add a system for that to the Mac. So that particular statement above is out of date, it is a part of the design now and thus something we’d like to add to Windows (though probably a little friendlier than asking people to know where their .exes are). It all depends on how easily we can access the Window’s record of what applications are available to view a particular type of file. From there we can build a simple per-file or Scrivener-global default handler for PDF, MOV or whatever.
But anyway, as I say, it’s on the list to at least look into. Thanks for the feedback, and explaining how in some cases this can be a necessity rather than a nice option. That really is too bad that they are taking advantage of the file association system on Windows like that. We and many other developers depend upon that being something you control and thus by extension giving you control over how our programs work.