Tablet [Q] Root not gained after following steps in post for Acer b1-A71

I've followed the steps on the post here: http://forum.xda-developers.com/show....php?t=2240029

And I've found that I can't directly comment on there and have to post in here "to defend from noobs". So.. yeah...

Hopefully someone can be kind enough to give me a little bit of a heads up - I've rooted Nexus devices successfully and built some of my own modified system images - Although I managed to flash a new firmware from the post above, as far as I can tell, the actual installation of a new rooted system image in the page above doesn't actually *do* anything...?

The process continues with "R......O.....O.....T" being displaced as a progress indicator but I didn't see any change on the device as it occurred (no restart in boot mode for instance).

I'm wondering if the "pre-rooted" images available on the page are infact, unrooted images.

Thanks in advance