ok, then probably things are more complicated: You need to adjust the setup sequence for the display controller.
Maybe this command has to be changed:
0x0a2, 0x04c, /* display offset, shift mapping ram counter */
But for this we probably would need to investigate the controller manual AND the display manual more closly.
A wild guess could be to set the argument to zero (or some other random values) and see what happens:
0x0a2, 0x000, /* display offset, shift mapping ram counter */
Oliver