After playing until about 3am EDT Sunday evening, I patched LOTRO roughly 12 hours later....monday afternoon.
It appears that the Update 5 patch (in addition to having an incredible number of "known issues" according to Turbine), does not run under CXG.... Update 5 had run fine under CXG in during the Beta prior to Thanksgiving.
PyLotRO, apparently after launching the LOTRO client displays a black screen. (Patching completes, and then the login information is accepted.)
No further details at this time...