After you have set up ftp access on your target machine, test it by using the IP address listed just below the options window. Make sure the FTP option is highlighted. the line will look like this:
"Other people can access your FTP server at
ftp://192.168.102.100/"
1. Highlight and copy this address;
2. Go to the Finder
3. From the Go Menu, Select "Go to Server" or CMD-Key K
4. Paste the ftp address into the Server Address field
5. Hit return or click on Connect
If you have anonymous ftp enabled, the machine should present you with a navigation window. Otherwise, it will ask you for a user name and pwd. Use your admin account - it should let you all the way in. Then, try it with CyberDuck. You should get the same result.
Although the MacOS supports ftp this way, I find CyberDuck to be much more stable, faster and safer to use. MacOS FTP tends to drop out and lose privileges as the connect ages, especially if you have a slow internet connection.
Just had a thought - your IP network number of the target FTP machine needs to be accessible from the other computer. If you have a router between your machine and the internet, you'll need to make sure you have a routable address assigned to the machine to make it visible on the 'net. If your router supports NAT (Network Address Translation) you can manually define a connection to the target machine. Your ISP (or whoever provided the router) can help you with that.
Hope this helps.