The generator matrix

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

generates a code of length 18 over Z4[X]/(X^2+2) who´s minimum homogenous weight is 12.

Homogenous weight enumerator: w(x)=1x^0+124x^12+722x^13+3074x^14+10306x^15+26883x^16+55844x^17+67766x^18+56484x^19+27042x^20+10074x^21+2974x^22+666x^23+124x^24+48x^25+10x^26+2x^28

The gray image is a code over GF(2) with n=144, k=18 and d=48.
This code was found by Heurico 1.16 in 90.4 seconds.