> the session is strongly linked to "age" and I don't want to annihilate my findings by adding "session".
Run two different models, one with and one without session. Then compare the two results.
Your specifications of -gltLabel 5 and -gltLabel 6 are not correct. You don't need to add anything through the glt option because those two interactions should be automatically included as F-statistics in the output.
Gang
