I finally mastered the act of downloading my phpBB forum but need to modify it with a different skin.

I have chosen the skin and downloaded and unzipped it to my own computer but can not work out how to get it into the files on the BV site so I can work with it.

As a long shot I opened Blue FTP and into the folder with the new skin in it on the let hand panel.
I opened the folder where the file must go to in the right hand panel.
I do not seem to be able to drag it accross. What other means is there to do so?
If there is a way to download 1 file directly from the phpBB styles site, I have not spotte it in FTP.