The generator matrix

 1  0  0  0  1  1  1  X  1  1  1 aX  1  1  1  1  1  1  1  0  X  1 aX  1 (a+1)X
 0  1  0  0  X  1 X+1  1 (a+1)X aX+1 X+a+1  0 X+a+1  a (a+1)X+a+1 a+1 aX  X aX+1  1  1 aX+1  1 aX+a+1  X
 0  0  1  0 (a+1)X+1  1 (a+1)X (a+1)X+1 aX+1 (a+1)X+a+1 X+a  1 aX  1 (a+1)X+1 (a+1)X+a  0 (a+1)X+a X+a aX a+1 (a+1)X  0 (a+1)X+a  1
 0  0  0  1 a+1  X aX+a+1 aX+a+1 (a+1)X (a+1)X+a+1  1 (a+1)X+1  X (a+1)X aX+1 aX+a X+a  1  0 a+1 (a+1)X+1 (a+1)X X+1 (a+1)X+a (a+1)X+a+1

generates a code of length 25 over F4[X,sigma]/(X^2) who´s minimum homogenous weight is 64.

Homogenous weight enumerator: w(x)=1x^0+1686x^64+7140x^68+15360x^72+24552x^76+15270x^80+1524x^84+3x^96

The gray image is a linear code over GF(4) with n=100, k=8 and d=64.
This code was found by Heurico 1.16 in 4.82 seconds.