Yeah, I hate to make an unnecessary thread, but a bunch of outdated links and vaguely labelled copies got me slightly confused.

Anyway, here is exactly how I solved it:

First, I flashed this exact image:
http://www.mrcrab.net/nokia/Nokia_N9...n=10.2010.19.1

which in turn allowed me to start the phone and access the terminal without having to enter a lock code.

Then I followed the steps from here:
http://lifewithmaemo.blogspot.in/201...lock-code.html

Which got me the lock code I needed in an instant.

I had issues with some of the other firmwares I tried. Most of them required the lock code on start, and one of them that didn't removed my IMEI number and wouldn't allow me to connect to the internet to install rootsh.

I hope this helps someone someday.