The generator matrix

 1  0  0  0  1  1  1  1  2  1  1  1 X+2 2X  0  1  X  1 3X+2  1  X  1  1  1  1  2  1  X 3X  1  X 3X 3X  1  1  1  1  1  1  X  2  1  0  1 2X+2  1  1 2X  2  1  0 2X  1 3X+2 3X+2  1 X+2 3X  1
 0  1  0  0  X  3 2X+1 2X+2  1 3X+3 X+2 3X+1  1  1 3X 2X+1 3X+2 2X+2  1 3X+2  1  1 3X  1 X+3  X  2  1  X 3X+1 3X+2  1  1 2X+2 2X+2 X+2 2X+1 X+3  1  1  1 X+2 3X 2X+1  1 X+2  0  1  1 X+1  X 2X+2  X  1  1 X+1 X+2  X 2X+2
 0  0  1  0  0  2  1  3  3 2X 2X+1  1  0 X+1  1  1  1 3X+1  0 2X+2 3X+2  X 3X+3 3X+2  1  1 X+2 2X+1  2 3X+2  1  3 X+1 2X  3  X  3 3X+1 X+3 3X+1 X+2  3  2  0  1  1 3X+2 2X+1 2X  1  1 3X+2 2X  1  1  1  0  1 3X+1
 0  0  0  1  1 X+3  2 X+1 X+3  X 3X 2X+1 X+3  0 3X+3 X+2 3X+2 3X+1 2X+3 X+2 3X+2  1 2X 3X+2 X+3  3 3X+3 2X+2  1  0 2X+2  3  X 2X+1 X+2 3X 2X+1 2X+2  2  1  2  3  1 X+1  X 3X+1 3X+2  2  1 X+3 3X+2  1 X+1 3X+3 X+2  X  1  3 2X+2
 0  0  0  0  2  0  0  0  0  2  2  2  2  2 2X+2 2X 2X 2X+2  0 2X+2 2X+2  2 2X  0 2X  0 2X 2X 2X+2 2X+2 2X+2 2X  0  2 2X+2 2X+2  0 2X+2 2X+2 2X+2 2X+2 2X+2 2X+2  2 2X+2 2X 2X 2X+2  2  2 2X 2X+2 2X+2 2X+2  2  0 2X  2 2X

generates a code of length 59 over Z4[X]/(X^2+2) who´s minimum homogenous weight is 51.

Homogenous weight enumerator: w(x)=1x^0+296x^51+1427x^52+3958x^53+7392x^54+13278x^55+20078x^56+28992x^57+35555x^58+39030x^59+37091x^60+29262x^61+20316x^62+13190x^63+6531x^64+3498x^65+1453x^66+518x^67+172x^68+60x^69+18x^70+6x^71+12x^72+6x^73+2x^74+2x^79

The gray image is a code over GF(2) with n=472, k=18 and d=204.
This code was found by Heurico 1.16 in 500 seconds.