I want to thank grif091 for all his help with this problem.
And let other users know what we believe is happening.
The EZX10RF is built on the Smarthome PLM module and some newer ones may come with extended memory. My EZX10 is very new so it may fall into this category. We believe the EZX10 is storing some of the link records in this extended memory. They are there, and working as they should, but the HSN Utility is not displaying them in the Manage Links tab. We expect that a future version of the utility will properly display these links. Since my motion sensors are working as I intended, I am just filing this away for future reference. If I do experience a problem that needs fixing, I hope the new utility is then available.