Okay first look in the matedit projects folder. In the projects folder there should be a folder with the name of the matrix you saved. Copy MDF and the bmp files in that folder into your darkbasic project folder. Then make a folder in your darkbasic project folder called Include. Put the Loadmatrix.dba in the Include folder.(If you don't know what the Loadmatrix.dba is look around the matedit folders. )Then in your game put this code.
#include "include/Loadmatrix.dba"
Dim BigMatrix(600,600,1)
Dim StartLoc_X(1): Dim StartLoc_Z(1):Dim Info(2)
Dim TArrayX(1): Dim TArrayZ(1): Dim FKey(10,1)
Dim ColData(100): Dim ZoneData(100): Dim Tiles(500,500)
Dim OverTexture$(100): Dim OverName$(20): Dim ReplaceTex(100)
Dim MOffsetX(25): Dim MOffsetY(25)
Dim MWire(20): Dim MGhost(20): Dim Lock(20)
Dim MatX#(20): Dim MatY#(20): Dim MatZ#(20)
Dim MatWidth#(20): Dim MatHeight#(20)
Dim TilesX(20): Dim TilesZ(20)
Dim MatHi#(20): Dim MatLo#(20)
Hope that helps.
Dont worry and keep a cool head.