I have the same problem.
I wanted to install PRS+ 2.0.12beta, but the update to 14080 didn't work.
I had to use the russified firmware with 14080 and then install 2.0.12beta.
Bought the 350 with a higher version than 08100 and I did a downgrade to 08100.
Since then I cant use the sony updater.
@jackie_w:
I tried to install PRS+ 2.0.12beta with 08100, but it said that I need the new firmware, so I think you need at least a newer firmware.
Sorry for my english, I'm from Germany
