I encounter the same problem.
My wan connection is PPPOE
lan gateway is 192.168.0.1
internal client's IP address is 192.168.0.223
the utorrent use port 56667, here is my nat config for utorrent.
/ip firewall nat
add action=dst-nat chain=dstnat comment=utorrent dst-address=\
!192.168.0.1 dst-port=56667 protocol=tcp src-address=!192.168.0.0/24 \
but the utorrent tells " Port is not open (you are still able to download)", what the problem of this nat config?
BTW, I don't want to use upnp.