Hi,
In the example given I've two remarks.
1. The path to the Memory initialization file is absolute, better to have a relative one
2. The hex file given doesn't work, so no UART output and no ("Spirit level" mode) but the remaining modes work since there are not related to the NIOS
I've attached a .hex file that is working (keep the example architecture).
Also for information I modified my system to use the SDRAM @ 150MHz and the NIOS @ 200MHz.
Regards,