You can purchase a Premium membership for only $35 per year, and this gives you access to download any or ALL of the over 400 add-ons developed for Xenforo 2.x. In addition, Premium members will get technical support. Once the Premium membership has expired you can continue to use the installed addons on your forum as long as you like.
1. When using the File manager, you will be copying files from your computer to XenForo cloud directory. So if you're asked to copy files which are located in an add-on directory, you will want to unzip the downloaded add-on on your computer, then copy those files using the File manager.
2. You can select an entire directory of files by pressing the shift button as you select the first and last file.