Hy, thanks for answering. Okay, when a 2-player-mode, also against another human player, is technically a problem on 8bit systems and when the game should be the same, on all systems, then sadly nothing can be done. It was just a suggestion, because in my experience (and i play Dr. Mario very often on different systems, e.g. on the SNES), playing against a human friend or against a good CPU-player, always is the most fun in these games. Because in the levels, the gameplay is always very similar, but directly against another player, the game has more dynamism, because it can become more interesting, thanks to the pieces, you receive from your opponent, when he make combinations.
I hope, that the rotation thing (possibility to turn in both directions) could be integrated, because this is an important feature, especially in higher levels of the game. Often it takes too long, to turn three times to the right, instead of one time to the left. Best regards.