My favorite way is to run the python script that comes with the license repair tool.
Download the License Recovery dmg file and carefully follow the instructions for Mac OS 10.7
I know it works, I have successfully recovered from a 150:30 before using this script properly.
I am having the same problem. I ran the python script, and have managed to open the repair tool but not to get it running. Any tips on what to do next? At this point I've tried about all of the solutions listed on that page.