[pst]

I find the folder navigation bar a bit confusing. When I'm at top level, it seems to show all the folders now, sorted by name. I can't really navigate trough my collection this way, it gives no hint of the actual folder structure.

Please have a look at the screenshot - "Book" is actually the root folder, that is currently selected. I think that one should always stay on the left side and on the right only the direct siblings should be shown. It could look like

"Books -> Digital Editions -> English: American literature English literature French literature ..."

Also it would be nice if the book view below could be configured to only show the books directly in the current folder. A more classic view option, so to say.