I downloaded and install the trial version.
After installation there were no lister or files listed. reinstalled. same problem.
See attached screen dump.
That's an empty tab. Navigate somewhere and you'll see files.
It's not a very intuitive start that you have there, but here are some things you can do to get started...
Up in the top, just above and to the right of the "Type" column header, you can click there and type C: to have it show you the C drive's root folder.
Also, try hitting F8. It should open a folder tree. (You can do the same thing via mouse by clicking up there where it says Lister and choosing Folder Tree.)
I hope this helps get you started.
If you need more help, feel free to post a new topic. (The preference is one question or topic per post. It makes it easier to find things later when people are searching for help.)