Exclamation [Q] Incorrect display size and resolution - how to fix?

After various (failed attempts) to build cyanogenmod for my device (RK3066 gem10313bk-rev2), I decided to try out a rom for a similar device.

After trying a few, I got this ROM to work almost completely: http://www.slatedroid.com/topic/3948...retina-tablet/

(using latest ver 8a)

The main problem is that the rom reports the wrong screen size and resolution.
The tablet is in fact a 9.7 inch (diag) with a resolution of 1024x768
Rom reports 5.1 inch (diag) with a resolution of 768x952

I've searched for fixes, but only found build.prop tweaks relating to pixel density (which I believe wouldn't really fix the issue).

Is anyone aware of the method I would have to use to edit the rom's reported resolution and screen size?