The generator matrix

 1  0  0  1  1  1  1  1  1  1  1 a^2*X  1  1  1  1  1  1  0  1 a*X  1  1  1  1  1  X  1 a*X  1  1 a^2*X  1 a*X  X  1  1  1  1  1  1  1  1 a^2*X  1  1  1  1  0  1  1  1  X  1  0  1  1  1 a^2*X  X  1  1  1  1  1  1 a*X  1  1  1  1  1 a*X  1  1  1  1  1  1  1  X  1  1  1  X  1  1  1
 0  1  0  0  X a^2*X  1 a^2*X+a a^2  1  a  1 a^2*X+1 a^2*X+1 X+a^2 a^2*X+a X+a^2  a  1 a^2*X+a^2  1 a^2*X+a^2  X a^2*X a*X+1 a^2*X+a^2  X X+1  1  0 a*X+a  1 a^2*X+a  1  1 X+a^2 a*X+a a^2*X+a^2 X+a^2 a*X+1 a^2  a a*X+1  1  1  X a^2*X a^2*X+a  1 a*X+a a^2  X  1 X+1  1 X+1  1 a^2*X+a^2  1  1 a*X+a a^2*X+a^2 a^2*X+a  a X+a a*X+a  1 a^2*X+a X+a a*X+1  X a^2 a^2*X X+1 a*X+1 X+a^2 a*X+a^2 a*X+a a*X a*X+1  1 X+1  0 X+a  1 a*X+a a^2*X+a a^2
 0  0  1  1 a^2*X+a a^2 X+1 a^2*X+1 a*X+1 a^2  0 a*X+1  a  X a^2*X a^2*X+a^2 X+a^2 a*X+a  a a^2*X+a a*X+a^2 a*X+a a^2*X X+a^2  a a^2*X  1  0 a*X+1  a a*X+a a^2*X  X  a X+a^2 a*X+a^2 X+a^2  1 a^2 a^2*X+1 a^2*X+a a^2 a*X+a^2 a^2*X a^2*X+a a*X+1 a^2*X X+1 a^2*X+1 a^2*X+a a^2*X+1  a X+a^2  X a^2*X a*X+1  X a^2*X+1 X+a  0 a*X+1 a^2*X a*X+a^2 X+1  a  X a^2  0  a  1 a*X a^2*X+a  1 a*X+a^2 a*X+1 a*X X+a a^2*X X+a  1 a^2*X+a a^2*X+1 a^2*X+1 a^2*X+a a*X a^2 a*X X+a^2
 0  0  0 a^2*X  0  0 a^2*X a^2*X a^2*X  X a*X  X  0 a*X a*X  X  X a^2*X  X a^2*X a*X  X a^2*X a^2*X a^2*X  0 a^2*X a^2*X a^2*X a*X a*X a^2*X  0  0  X a^2*X  0 a*X  0 a*X a*X a^2*X  0  X a*X a*X  X a*X a*X  X  X  X  0  X a*X  X  0  0 a^2*X a^2*X  0 a^2*X a^2*X  X a^2*X  X  X a^2*X  0 a*X a*X a^2*X  X a*X  0  X a*X a*X a*X  X a^2*X a*X a*X a*X a*X a*X a^2*X a^2*X

generates a code of length 88 over F4[X]/(X^2) who´s minimum homogenous weight is 252.

Homogenous weight enumerator: w(x)=1x^0+1134x^252+3165x^256+3276x^260+2844x^264+2196x^268+1656x^272+1164x^276+708x^280+198x^284+42x^288

The gray image is a linear code over GF(4) with n=352, k=7 and d=252.
This code was found by Heurico 1.16 in 2.95 seconds.