What you see is normal for both FTP protocol and your hosting.
FTP protocol uses 2 sets of ports. One set of ports is for "control connection"(in your case port 21) and another set of ports for "data connection".
Control connection port is used for sending commands to an FTP server and getting status replies back. The actual file transfer and directory listing is being transmitted over data connection ports. This is what those PORT and PASV commands you see your ftp client use.
Based on the information you provided, you sounds like your ftp entry is configured with PASV mode. When FlashFXP sent that command to your server, it replied back asking to connect to its port 54675. These numbers will (almost) always be between 1024 and 65565.
As for the hostname, you originally connected to your server using your domain name. Your firewall knows nothing about that domain, it just sees a connection attempt to an IP address. To present that information in a more readable format, your firewall tried to convert that IP into a hostname and it got that ekiaiokqii.c08.mtscv.net entry.
What that means is there's a dns mismatch between going from hostname to an IP address and going from IP address to a hostname. This is not necessarily wrong/bad. It all depends on your hosting plan and the way your hosting provider configures its network.