Why is the Network Link Conditioner preference pane crashing as soon as I turn it on? I am trying to use the Network Link Conditioner preference pane included with the Hardware IO tools in the developer tools to throttle Internet speeds. I can open and load the preference pane, but as soon as I try to turn it on, System Preferences crashes.

Why is this happening and how can I fix it? I have a 13" MacBook Pro with a 2.3 GHz Intel Core i5 running OS 10.7.3.
Here's the log entry for the NLC crash:

5/10/12 9:31:39.150 AM [0x0-0x1c51c5].com.apple.systempreferences: NLCd : Bootstrap failure
Just a quick note to say that I eventually stopped the crashing by manually copying these two files from another OS X machine and then manually starting the nlcd daemon
(if you don't have another Mac, I posted my copies of those files here)

Copied these files:
/System/Library/LaunchDaemons/com.apple.NetworkLinkConditioner.plist
/usr/libexec/nlcd
Run these three commands:  

sudo chown root /System/Library/LaunchDaemons/com.apple.NetworkLinkConditioner.plist      
sudo chmod 644 /System/Library/LaunchDaemons/com.apple.NetworkLinkConditioner.plist   
sudo launchctl load /System/Library/LaunchDaemons/com.apple.NetworkLinkConditioner.plist


After that the pref pane didn't unexpectedly exit when moving the switch to 'on'.

Taken from https://devforums.apple.com/message/645980#645980