This is a fabulous tool. One "feature request" I would love to see is a favorites list. The recent list is great, but since it tracks every folder visited, it can fill up fast with the intermediate folders needed to navigate to your new destination. Given that I frequently need to shift between widely separated directories on network shares and local drives, having a favorites that I could just use to hop to at least the approximate location would be great!
Sorry for the delay -- somehow I missed your question.
Yes, you can show only folders by entering '^' as the regular expression filter. That will cause the program to display only files that begin with nothing. Since no file has no name and folders are exempt from RE filtering (by default), only folders will be displayed.
I realize that's a bit of a hack so I will consider adding such a feature.