The folder resource has numerous accessibility problems with it. I'm not sure if it is easier to redesign the resource or to apply patches to fix it. Here are the issues.
1. The file list is not keyboard accessible because users need to use a mouse to download the file. (screen reader users can actually download the file because of the way screen readers work with Web pages)
2. There is no indication to screen reader users that folders with sub-folders have expandable and collapsible nodes.
3. The file organization (how folders are stored in subfolders) is only known through visual cues. There is no semantic structure underlying the listing of files to know where all of the files exist in relation to one another.
4. The dashed lines used to denote the file hierarchy for sub-folders is read by screen readers as being a link instead of just a graphic.