Quick traffic shaping question

[kage]

I am fairly new to traffic shaping and am having a little difficulty:
in short my girlfriend allowed her friend who lives next door onto our network, however she downloads/torrents all the time.
instead of being rude and kicking her off the network i really just want to penalize her and cap her at about a megabit/s
my internet connection speed is 15megabit/s down and 1.5megabit/s up
my lan is gigabit

i have run through the traffic shaping wizard and only really enabled penalization. i use bandwidthD to check on usage and it seems to have worked, she hasn't gone significantly over 1Mb/s since enforcing the traffic shaping. I have tested this by assigning myself her IP address then running just a quick online speedtest, i get about 1Mb/s when using her ip (traffic shaped), and slightly over 15Mb/s when using any other IP.

the problem i have run into is that i noticed a severe decrease in all local traffic, a little investigation shows that all lan traffic is being shaped to 15Mb/s, i will attach screenshots of my setup.

all i really want to do is have the traffic shaping only apply from a specific LAN address <=> wan.

any help would be appreciated. :)
thanks
kyle