Hi,
Please find my response below:
1) Do I need to integrate the Remote Upgrade IP in the factory design with a state machine that operates it according to page 7 in the user guide ?
Yes, you need to.
2) I'm working with a EPCS128 device so what are the address range of page 0 (the factory image) and page 1 (image 2-application image) ?
I am assuming you are using Active Serial Configuration Scheme. When you are generating the bitstream for the flash (.jic), you may need to add 2 sof file (factory image and application image), from there, you can select the start address for page 0 and page 1.
Regards,
Bruce