How to add brand logo and description at the category page?
To add brand logo and description at the category page with the help of Improved Layered Navigation please:
1) Open admin > catalog > improved navigation > filters > manufacturer
2) Set property "Show on List" to "Yes", save the filter.
3) Open the filter again, switch to the tab "Values", select a value, say "Nike" and upload the brand images (3 sizes)
4) Clear the cache.