Serial configuration problem of Cyclone II device using quatrus 9.1

I have exactly the same problem : EP2C20 project builds with V9.0sp2 and no problem configuring, builds with 9.1 and device doesn't configure.

I did notice that the assembler report file with 9.0sp2 has "Info: Active Serial Mode CONF_DONE pin error checking is disabled", but that's not there in the 9.1 rpt file.

So far, I haven't found what this means and if/why this mode became enabled in 9.1, or how to disable it.

It's a pretty glaring testing failure - mainstream devices just won't configure with the new version.....oh well, I guess that's the price we pay for the new "pastel shades" in the splash.