Using this extension you can do the following tasks:-
1) You can import any number of images for any type of product whether it is simple,downloadbale,configurable,virtual etc.
2) You can assign any number of images to a product and choose which product should be a base image, small image, thumbnail.
3) Apart from the selected base,small or thumbnail images the other iamges will be listed in product detail page as the extra images for that product.
4) Put your images that you want to import inside import folder inside the media folder.
5) Your csv file name should have "_imageupload" string in file name, like mobile_imageupload.csv,sports_imageupload.csv etc
You need to put images inside Root/media/import/ folder and give read write permission to import folder.