If you've downloaded skin (file with .ztr extension) on you PC and want to install it to Tracker you should beam this file to your device with Infrared or with Bluetooth or email.
When the file is received just press "Done" and it will be saved to Inbox.
Then select "Import skin command" in Tracker and you'll see a list of skins found in inbox and select one of them to import.
Now you can delete the beamed file from your inbox in order not to waste space on your device (Messaging application, Beamed folder, select needed message and use "Delete message" command in the menu).