Could you show the contingency table about Task and Gender? You can find it on the terminal when you run your 3dLME script.
The empty space after the positive (+) and negative sign (-) should be removed in your original script:
-gltLabel 4 'efnback_vs_rest' -gltCode 4 'Task : 1*efnback1 + 1*efnback2 - 2*rest' \
-gltLabel 5 'dynface_vs_rest' -gltCode 5 'Task : 1*dynface - 1*rest' \
-gltLabel 6 'reward_vs_rest' -gltCode 6 'Task : 1*reward1 + 1*reward2 - 2*rest' \
-gltLabel 7 'Negurg_mc-efnback_vs_rest' -gltCode 7 'Negurg_mc : Task : 1*efnback1 + 1*efnback2 - 2*rest' \
-gltLabel 8 'Negurg_mc-dynface_vs_rest' -gltCode 8 'Negurg_mc : Task : 1*dynface - 1*rest' \
-gltLabel 9 'Negurg_mc-reward_vs_rest' -gltCode 9 'Negurg_mc : 1*reward1 + 1*reward2 - 2*rest' \
Gang
