Sony has released a list of PlayStation games that experience compatability problems with the backwards compatability feature of the PlayStation 2. Mortal Kombat Trilogy for PlayStation is one of the nine games on Sony's incompatability list. According to GamePro's Dan Elektro, MKT crashes when the "Press Start to Continue" counter reaches zero. That is the only problem that has been found so far.
If you experience any other problems with MKT PSX on the PlayStation 2, hit our message boards and let us know.