I'm not sure if you can store a string into a pointer to a char (but point to its address). And definitively I'd use C string functions to compare them, rather than '='.
Please check this working one, based on yours:
#include "DarkGDK.h"
void DarkGDK ( void )
{
dbSetTextSize(8);
dbSetWindowSize(1000,1000);
char answer[256]; //instead of char *answer;
char mmm[256]; //instead of char *mmm;
strcpy(mmm, "m2zt\0"); //instead of mmm = "m2zt";
while ( LoopGDK ( ) )
{
dbPrint("Answer?");
strcpy(answer, dbInput()); //instead of answer = dbInput();
if (strcmp(answer, mmm)==0) //instead of if (answer == mmm)
{
dbPrint("Correct!");
}
else
{
dbPrint("Incorrect!");
}
dbPrint();
dbPrint("--Press a key--");
dbWaitKey();
dbSync();
}
}