Image Select Capability?

1: yes. our current cyclone board has a custom loader CPLD design

that supports multiple images. the loader part fits into a EPM3128.

2: In the flash where you load the image from.

You could also use the UFM of a MAX II (non ES device assumed)

4: Didn't delve into AN346, but if you want to support AS from an EPCS

as well, the loader CPLD has to tristate all config outputs to the FPGA,

or else they would contend.

5: This is covered in the datasheet. TDO,TMS up / TCK down / TDO open

6. Yes

Cheers, Roger