Problems exporting motions from Animator to Viewer

I have made a number of animations with an original character, but am having trouble exporting them. When I bring the .mtn files into the Viewer, only some of the model moves. For example: the arm and hand are both animated, but only the arm will move. All motions work properly within the Animator program.

I have tried multiple settings when exporting from the Animator, but nothing has worked.