I'm having a hell of a time trying to port it over as well. I've tried porting it over using the 4.2 framework/tw-framework and editing the manifest with no luck. I imagine it could have something to do with down-porting it from 4.3, or maybe it's hard-coded to fit the GN3's bigger screen.
As someone stated above, the modded 4.2 android keyboard (AOSP or AOKP, can't remember) that comes in the latest version of Hyperdrive is pretty nice - and has the number row as well. However, I would still really like to get the GN3's keyboard working! If anyone has any tips on how to port keyboards, don't be shy!