I have several questions regarding 2nd level analysis.

1. Error message pops when I try to do ICA network analysis.
I already did voxel-to-voxel analysis and can access to the result;however, the error message says that I have to run voxel-to-voxel analysis first. What should I do?

2. I want to be sure about covariates for the analysis.
I put subject effects as follows.
Pre_G1 = [1 1 1 0 0 0 0 0 0 0 0 0]
Post_G1 = [0 0 0 1 1 1 0 0 0 0 0 0]
Pre_G2 = [0 0 0 0 0 0 1 1 1 0 0 0]
Post_G2 = [0 0 0 0 0 0 0 0 0 1 1 1]
Age = [70 80 80 90 80 70 60 70 80 80 90 80]
(1) If I want to compare Pre_G1 and Post_G1 while controlling Age and Sex, is it correct to select Pre_G1, Post_G1, Age and set 'between-subjects contrast' as [1 -1 0] or [-1 1 0]? 

(2) What if I set between-subject contrast as [1 1 0] or [1 0 0; 0 1 0]? I don't understand differences among these set-ups.

(2) If I want to compare Pre_G1 and Pre_G2 while controlling Age and Sex, is it correct to select Pre_G1, Pre_G2, Age and set 'between-subjects contrast' as [1 -1 0]?