Start 1964 with Rice video DEBUG plugin, you will see a DEBUG window open when you open 1964.
1) Start your game
2) In the DEBUG window, you can use the Pause button to pause at a certain point of the game. Press the "Go" button to resume. You can also use the "Pause At Next" button to pause at next n event, and you can put a number in the empty box next to the "Pause At Next" button, and you select an event in the list.
2) When the game is pause, you can dump the current texture. In fact, you can dump the whole list of things by selecting in the list next to the "Dump" button.
3) All the check box options allow you to turn on/off logs of different type of events during the game play.
4) The "Clear" button will clear the log window.
5) The "Update" button will redraw the screen upto the last drawing command.
For you, you can use the "Pause At Next" button as the step by step button.