Program EPCS with 2 Nios II Images

Switching between images can be done using remote configuration, because it lets choose load address from EPCS or CFI. Here http://www.grigaitis.eu/?p=514 is nice description of remote configuration. There is:

int CycloneIII_Reconfig( int remote_update_base, int flash_base, int reconfig_offset,

int watchdog_timeout, int width_of_flash );

function that switch between images, you just need to use default image that will be loaded first. Moreover both images must have remote configuration and both of them should have button reading function that show when you need to switch image.

Here need only imagination..