Pull images from single post or category using Easy Nivo Slider

I am try to use the slideshow widget in the Easy Nivo Slider to pull images from a “single post” or posts that have a certain “category” name.

I can’t seem to get that to work right. It either shows “no images available” or it will try to pull images from “any” post.

The codes gives something like this, but I can’t figure out if you can just have it show the source as a post name, or just from posts that use a category name:

[nivo source="current-post" size="widget" speed=3000 pause=5000]

Any help would be appreciated.