Yes, you can use multiple images in a source via the Image Slideshow plugin.
To do this, simply click Add > Other > Image Slideshow…
Then click Add and choose the images you want to use:
You can also choose the transition you want to use:
how you want it to loop:
And how long you want the interval between images to be:
When you are done, click Ok to save it.
You can now use the plugin to display multiple images in one source.