The generator matrix

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

generates a code of length 15 over F4[X,sigma]/(X^2) who´s minimum homogenous weight is 32.

Homogenous weight enumerator: w(x)=1x^0+48x^32+12x^33+267x^36+144x^37+192x^39+1455x^40+648x^41+1152x^43+4131x^44+1296x^45+1728x^47+4059x^48+972x^49+201x^52+69x^56+9x^60

The gray image is a linear code over GF(4) with n=60, k=7 and d=32.
This code was found by Heurico 1.16 in 0.194 seconds.