See the GM Guide - Gameplay : Images entries in the user guide in the Library (link at the top of this page) for more information on using images.Quote:
Originally Posted by DwarfLord
You could put them in the images directory of the specific campaign you are running, but you would have to do this for each campaign and you would soon end up with a big long list of images which might get hard to manage.
The images list in the FG campaign does get refreshed when you open the images list window. So, for images like these above (encounter images that could be used for random encounters) it is a good idea to store them in a seperate folder somewhere and then just copy the required image into the \images folder of the campaign you are running and then close/open the images list window and your image will be there ready to use - this can be done while running a game.
However, if you are using an image for a planned encounter, it is good to put it in the campaign \images folder beforehand and setup your encounter (grid, NPC placement, etc.).