When NcFTPd is run, it requires two command line parameters. The first is the pathname to the general configuration file, known as the general.cf file. The second is the pathname to the domain-specific configuration file, known as the domain.cf file. The general.cf file contains all of the NcFTPd settings that apply to the entire server, while the domain.cf file contains sets of configurations specific to each domain.
To create these files, you copy the samples from the distribution, so to create the general.cf file, first copy of the general.cf-dist file that came with the package, and similar for the domain.cf file.
There should be enough information in the sample files to configure the server without delving too deep into the documentation, but detailed information for all the configuarable settings are available.