Clicking on your link gets me a "Forbidden" message.
In the LFSLapper files, open the /default folder/directory, then the /includes folder/directory.
In there, you'll find a file called addonused.lpr
Open with a notepad type editor (Notepad, PSPad, etc).
Look for a line that has #include( "./driftmeter.lpr");
Remove the hash (#) symbol from the front of the line (hash is like a comment symbol and tells LFSLapper to ignore everything in the line after it).
When your new line reads include( "./driftmeter.lpr");, then save the file, and restart LFSLapper.
You will still have to amend $DefaultTopCar in the lapper config file if you want to see more than one car when looking at who's top.