Firewall slows down traffic

Hi all,
I’m having a performance problem with the firewall: I have a local gigabit network, but after installing Comodo the transfer speeds are limited to ~140 Mbit/s. When I transfer files, the task manager shows 50% CPU usage (I have a dual core processor, so that equals to taking all the processing power of one of the cores).

Is there a way to completely disable the firewall on this local zone? I tried to set the firewall security level to “Disabled”, but even that doesn’t help at all, so I’m a bit pessimistic about this.

Please tell if you have any ideas. I quite like the Comodo firewall, so I’m not very keen to look for alternatives.

Best regards,