I'm up to the same task with a handful of boards related to some movies I
really enjoyed.
I'm a newbie myself, this is the way I figured out to get the job done without
downloading gigabytes of unnecessary crap
You go with
2	Mirror Web Site(s) with Wizard
using the url of the board (e.g. http colon //www. imdb.
com/title/tt1128075/board/)
and choose Wildcards (return=none) :-*.jpeg -*.jpg -*.gif

Let me know if you find a better working solution!!