It's pretty cheeky to be demanding payment when you haven't answered the question.
Check out the PDF link.
A figure 8 is one of many possibilities of ‘restricted’ orbit values.
The most common orbit is to have the planet orbiting well outside of both stars.
He answered it in post 13. The planet will orbit the point around which both stars also orbit. Since the two stars are fairly close together, the planet will orbit outside both of them, and will have a fairly eccentric orbit. If the stars are widely separated, a figure-8 is possible, though very unlikely.