A very odd device. Two hours later, you may have a large circle cutout.  That is, if you don't give up and get the jig saw out to finish the cut. 

 In your pictures, I don't see a set screw on the stop collar.   Can the depth of the drill bit be adjusted? Without being able to adjust the depth, I don't see how you would get it started so you must be able to adjust it.   The patent shows it is fixed but the verbiage says it could be adjustable.  From the patent drawing, it looks like the bit is supposed to be a down-cutting bit.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.