Using alt_flash_open_dev with 'enable_reduced_device_drivers'

From what I've read, implementing the CFI interface doesn't look too bad, but getting the timing to work could be problematic..

Interstingly, without enabling the reduced driver option, the program size is 149KB, so a little more than twice what I've created in qsys.

However, the compilation report shows logic utilization is < 25%, and memory utilization at 33%.. unfortunately, if I try increasing the onchip memory size, the design doesn't fit! In theory there's enough memory there, but yet it won't synthesize a contiguous space larger than 69KB.. why?