Update: It seems that my bookmarklet did not work in every browser, as Flick renders the sets differently in different browsers. I updated the code and it should now work.
The problem was that when you want to add photos to a Vimeo video all it accepts is a comma separated list of either URLs or Flickr Photo IDs. I already had made a set on Flickr of the photos I wanted to add and adding all those 18 URLs by hand was just too much work
So I got thinking: why not make a bookmarklet that gets all the links of the images in the set from the page, and outputs them to the user as a comma separated list? Although I have never done something like this before, it only took me a few minutes to build this and the result is the following link.
Using it is very easy. Just drag the bookmarklet into your bookmarks-bar. Now when you want to add all the photos from a set to your Vimeo photo, go to the phoo set on Flickr and click on the bookmarklet. This will give youa popup with a long code of text. Copy and paste that text into your Vimeo text boxx for photos and submit.
The code has a few small issues. First of it returns URLs, not Flickr Photo IDs. This doesn’t really matter but it would be more human-readable maybe. Secondly it doesn’t catch if it is on a Flickr site at all. I might change that in the future but probably won’t. If you want to make your own edit, you can download the source from here.