I'm not sure what you mean it's doing a forward. What are you entering for hostname?
I don't have any plugins needing updating at the moment so I can't see the dialog that it presents but it was pretty simple to use. If I'm not mistaken it only asks for 3 pieces of information.
hostname - ftp.you-TCH-domain.ext
ftp user - the ftp user you created
password - the password for the ftp user you created
And a drop down box to remember the password.
As I said I manage 6 WordPress blogs and use the feature all the time so I know it works.