The generator matrix

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

generates a code of length 51 over Z4[X]/(X^2+2,2X) who´s minimum homogenous weight is 42.

Homogenous weight enumerator: w(x)=1x^0+259x^42+726x^43+1216x^44+2026x^45+3028x^46+3976x^47+4948x^48+6084x^49+6697x^50+7044x^51+7164x^52+6282x^53+5211x^54+4132x^55+2898x^56+1722x^57+1034x^58+606x^59+232x^60+140x^61+49x^62+28x^63+21x^64+2x^65+10x^66

The gray image is a code over GF(2) with n=204, k=16 and d=84.
This code was found by Heurico 1.13 in 44.6 seconds.