The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  X  X  1  X  1  X  X  1  X  1  0  X  1  1  1  1  0  X  X  0  X  X  X  0  0  0
 0  X  0  0  0  0  0  0  0  0  0  0  0  0  0  0  X  X  0  X  X  X  X  X  X  X  X  X  X  X  X  X  0  0  0  X  0  0  X  X  X  0
 0  0  X  0  0  0  0  0  0  0  X  X  X  X  X  X  X  X  X  X  0  X  X  X  X  X  X  0  X  0  X  0  X  X  0  0  0  X  0  0  X  X
 0  0  0  X  0  0  0  X  X  X  X  X  0  X  X  0  0  0  0  0  0  0  X  0  X  0  X  X  X  X  X  X  0  X  0  0  X  X  0  0  0  X
 0  0  0  0  X  0  X  X  X  0  0  0  0  X  X  X  X  0  X  0  X  X  X  0  X  X  0  0  X  0  0  X  0  0  0  0  0  X  X  X  0  X
 0  0  0  0  0  X  X  0  X  X  0  X  X  X  0  0  X  0  X  X  0  0  0  0  X  0  0  X  0  0  0  0  X  X  X  X  X  X  0  0  X  X

generates a code of length 42 over Z2[X]/(X^2) who´s minimum homogenous weight is 40.

Homogenous weight enumerator: w(x)=1x^0+93x^40+31x^48+3x^56

The gray image is a linear code over GF(2) with n=84, k=7 and d=40.
As d=40 is an upper bound for linear (84,7,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 7.
This code was found by Heurico 1.16 in 68.1 seconds.