BTW I am using Sim 2013 SP5 for this, to maintain compatibility with other users in our organization who have not moved to newer versions. If necessary, I can move to 2014 with care.
The change from sharp edge to a radius worked, though the required radius is substantial - So far I have not made anything run correctly unless the element size did not exceed the radius; this applies to the element size of both the rounded edge and the contacting planar surface. This is large enough that I will have to tweak my model to compensate for dimensional changes (ie the loss of interference) caused by the application of the edge radius.
shrink fit should work fine here
nonlinear would be a better option for capturing the contact