The generator matrix

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

generates a code of length 76 over F4[X,sigma]/(X^2) who´s minimum homogenous weight is 224.

Homogenous weight enumerator: w(x)=1x^0+45x^224+48x^225+144x^227+558x^228+144x^229+48x^231+9x^232+3x^236+18x^240+3x^244+3x^256

The gray image is a linear code over GF(4) with n=304, k=5 and d=224.
This code was found by Heurico 1.16 in 0.078 seconds.