The generator matrix

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

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+654x^16+768x^18+608x^20+16x^24+1x^32

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 5.28 seconds.