how to import gallery images with csv

Just to clarify, I assume you are using the Import/Export module, NOT Dataflow. If you have been using Dataflow please try the same process with Import/Export module and see if your results improve.

This is definitely standard functionality - please see my linked CSV export from a fresh install of Magento CE 1.7.0.2 with sample data installed. Do a search for small_image and you'll find the correct columns:

image_label, small_image, small_image_label, thumbnail, thumbnail_label

There are also these columns for controlling the media gallery:

media_gallery, _media_attribute_id, _media_image, _media_lable, _media_position, _media_is_disabled

The Magento import/export is tricky, there's no two ways about it. There's basically no documentation and some quirks/bugs that can cause unexpected results. Everyone who knows how to use Mage_ImportExport has most likely spent hours crying into their keyboards at some stage.

That being said, it does work and it does work well once you know the tricks. If you could post your CSV here and maybe tell us if you've made any customisations to your Magento installation then the community will be able to better assist you.

Also, make sure you are not ticking any of the attribute 'skip' checkboxes when you are performing your export.

Just add the following columns to your import CSV

image_label, small_image, small_image_label, thumbnail, thumbnail_label

And set the respective image paths to be relative to ./media/import . Eg

image_label, small_image,
"my_label",  "./img.jpg",

Then upload all your images to be in ./media/import

Categorising imports

If you want to categorise the images, just put them in a sub-directory in ./media/import - and set your path in the CSV to include it.

Eg. You uploaded your images to ./media/import/20130304
So the image path would be ./20130304/img.jpg