Helping making blog private while using wp-filebase

I’m trying to use wp-filebase with my private blog (I use the “Members” plugin to make the blog private), and I want the users to be able to download files which I have in the blog (I use wp-filebase download manager). The problem is that I keep getting “file not found” error unless I delete the .htaccess file, but that’s no good because I want the files to be hidden to the public. I’m a noob, so please help me step by step, thanks!

http://wordpress.org/extend/plugins/wp-filebase/

http://wordpress.org/extend/plugins/members/