Well I called MTH customer support today,
and there is a way to reset the address to factory default 3.
set the engine on the main, enter up loco #55, to into
program on main. program loco 55, CV 55 with a value of 55.
exit out and call up loco 3,   preform start up and it should work.
Worked on mine.  If you want to re enable long addressing 
at this point, go back into programing for loco 3, 
at CV29 enter a value of 38.