I used MakeHuman to create Jesus and the disciples.  There was a small delay after installing MakeHuman, apparently due to a conflict with python libraries.  I found that if I ran MakeHuman with Administrator rights, I avoided whatever the problem was.  The learning curve was fairly steep but at the end I created a custom character, fully rigged and imported into blender in about 20 minutes.  Interestingly, with Blender set to imperial units, I needed to export the MakeHuman models with the units set to 'meters'.   Below is the current scene with bodies roughly positioned.  (CAUTION:  Partial Nudity - May not be appropriate for children under 53 years. ;) ).

While recreating famous paintings, it is interesting to find that even the great painters were not perfect (I guess that is what makes it art!).  After modeling the Upper Room and positioning the Disciples, I discovered Leonardo Da Vinci didn't get the perspective quite right; the side walls need to be a little wider to accomodate the Disciples at the end of the table!  I will probably end up flaring the walls near the table to match the original as closely as possible.

Here's the main camera shot of the table with a smattering of props. 

Now that the people are in place, all I have left is creating their clothes and adding hair.  Shouldn't take more than another day or two!  My goal is to have the clothes roughed in within two weeks with another article highlighting the progress.   Wish me luck!