The generator matrix

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

generates a code of length 18 over Z4[X]/(X^2+2) who´s minimum homogenous weight is 16.

Homogenous weight enumerator: w(x)=1x^0+395x^16+320x^17+648x^18+320x^19+340x^20+8x^22+16x^24

The gray image is a code over GF(2) with n=144, k=11 and d=64.
This code was found by Heurico 1.16 in 47 seconds.