now I've got a clue of what you mean.
If you want to upload files in backend as e.g. SuperUser you have to follow these steps:
First go to Components -> Phoca Download -> Files
Now it depends on how you want to upload your files.
You can upload your files by either ftp (you should be aware of access rights on your server etc.) or from inside phoca download.
Let's assume you want to upload files from inside phoca.
Click on "Multiple Add" in the phoca menu bar.
In the right pane select a folder (and/or create a new one) in which you want to upload the file.
Click the "Upload" tab, select the file to upload and click "Start Upload". (Remember the folder.)
Because there's nothing to save click "Close".
Back in "Files" click new and enter all the information you need for your file description etc.
From the field "Filename" select your uploaded file.
Enter the appropriate values in the "Title", "Category", "Access", "Uploaded By" and "Owner" fields.
Click "Save".
That's it (I hope)...

This description is based on my own experiences.
Regards Mike