Can I somehow download with FlashFXP at a different port?

[MxxCon]

there are 2 types of connection in ftp protocol.
control connection is the connection made to ftp port(often 21) can be any port, is where you communicate with ftp server.

data connection, is the connection made between client and server or server and server is where directory listing and data being transfered. this connection can not be below port 1024.
check out http://slacksite.com/other/ftp.html it nicely explain how ftp works