One more step

Check your inbox.

I've just sent you an email from tim@polymathematic.net. Click the button in it to confirm your address; that's what unlocks the download and keeps you on the list. If it isn't there in a few minutes, check Promotions or Spam, and drag it to your inbox so the next one lands where it should.

If you signed up for the free course, the video walkthrough and quiz are waiting at courses.polymathematic.net; the email has the link.