No, there is not error with the texts of the checkbox. ;)
In fact, with your configuraion, the server never seethe domain names so enter "dlinkddns.com" in the filter, is useless.
I think that the right filter to be used with your configuration is "192.168.2. 178.63." (first mask for internal access and 178.63. for net2ftp).
Note : maybe the ip address for net2ftp isn't the same from germany. See your log file to check this one
Good sunday