Just to let you very helpful folks know - my "challenging" student came to class last night (for the first time in several weeks), and I was able to put your suggestions into practice when teaching him.
There were 3 students, so I was able to let the other 2 get on with the technique while I took this one aside to run through the basic moves solo, before plugging him back into the group. During group training everyone was told to go slowly, so nobody got to throw anybody else too hard.
Finally, awkward student decided to make life difficult as uke during ai-hanmi nikyo, turning away from nage. I showed the other students how to counter this (stepping around uke) using Mr Awkward as uke, and surprise surprise he stopped turning away and started to follow the technique
We also worked on drawing uke in using a downward spiral, so turning away simply wasn't an option for uke. They all picked up on it very well.
So I'm very happy to report that the class went extremely well, everyone improved, and Mr Awkward simply didn't get the opportunity to make life difficult for himself or anybody else
Thanks again for your help guys - it really made a difference in class last night!