Setting up FTP server on ReadyNAS OS6

We have set up an ftp server on our PC using FileZilla that successfully receives log files from our sites around the country. The clients at the sites, send the data themselves to our external IP, they are port forwarded to our PC where FileZilla recognises which group/user they are (info also entered in at the client end) and places their logs into their associated folders.

These logs are not very important information so security is not a primary concern for us.

As the data does not need to be accessed often, we would like to alternatively set up our ftp clients to send their logs to the ReadyNAS we recently had set up in our office, and I have attempted to do this, but with limited success. I have followed the logical steps to emulate what we did to set up the FileZilla ftp, but I've yet to get the ReadyNAS working with this.

We have changed the port forwarding on the router from the previously successful forwarding to our PC, to the readyNAS. The ports 20-21 on the router are forwarded to 20-21 on the readyNAS, and ports 11,000-12,000 (ports previously successfully used with FileZilla) are forwarded to 32768 - 33768 (default ports on ReadyNAS ftp options, which will not allow me to change to 11,000-12,000 so that is why the ports 11,000-12,000 are forwarded to 32768-33,768).

I have created users on the system which match those sending out the data at our sites e.g user: "site1", password: "password001", which match up to the clients sending them out and have given these users the access (file and network) priveledges to the equivalent folders in the ReadyNAS, yet despite this I cannot get the ftp data to be received successfully. I have tried both "anonymous" and "user" mode.

Here are screenshots of the settings that I am currently using:

Client Settings:

Port Forwarding:

NAS ftp Settings:

I hope you can help us with our problems and working out why the files are not being transferred.