NiosII and DDR2 simulation issue

Haha, it is true, the one that you mention is the DDR2(7.2) High Performance controller not the older DDR2 controller (still provided in 7.2). In the old legacy ddr2 controller, user need to specify more timing information in the settings window, but the new DDR2 core use the trainning sequence to adjust the timing automatically by reading and writing to the first few bytes in the memory.