I just tried Core FTP 1.2 Lite because it claimed to have bandwidth control. So, I tried changing the recv and send sizes to 35000 (approx 35KB/s) and later altered the values (both) to 1000. Core FTP still however was using my entire bandwidth (64KB/s), independent of how the recv and send fields were set (connected to ftp.sunet.se, downloading RedHat's most recent Linux distribution).
Hence I uninstalled the FTP client since bandwidth control was the main reason for installing it.
I will consider installing a bug fixed version when one exists or when you have proven that it is all my fault

/ Regards, Peter