Nitro Support provided me with links to Nitro Version 12.10.1.487 which solved the problem.
They recommended the following direct links for installing 12.10.1.487:
x32 http://install.nitropdf.com/professional_12101487/en/burn/nitro_pro12_ba_x86.msi
x64 http://install.nitropdf.com/professional_12101487/en/burn/nitro_pro12_ba_x64.msi
They may have a different version now but the above links fixed my problem and the case was closed. Hope it helps.
Curt G.