ok, never mind. i figured that one out.
next question: using the back office, how do i purge all hits from a given IP? or do i need to do that directly?

You can sort hits by IP then delete them one by one. If you use Firefox you can also use the "Snap Links" add-on to right click and drag over a bunch of links to open them in new tabs. I've used that to delete bunches of hits "at once", but if you've got a lot of hits to get rid of it's probably easier directly through the database.