I only applied the mods that Blaizzen did last night for the first time (been putting it off for some time). Anyway, the Wiki was reasonably simple to follow, although there were no instruction on how to use Ovi Maps with voice guidance.

To get it to work after substituting index.html, installing maps and voice files, in addition to OMVoiceServer, I planned a route, hit the red dot to lock on to my current position, and started driving. First go never worked, as I never had OMVoiceServer running (not sure if you have to either), so I exited Ovi Maps, started OMVoiceServer, and tried again. This time I got about half of the voice instructions spoken, provided I stayed on the route.

Once I deviated from the route, I recalculated by tapping the circular arrows and it gave me the route that I was on. However, the voice guidance seemed to stop after a couple of recalculations.

Hats off to Blaizzen, fantastic job finishing Nokia's work. I'll try and get some more testing in and a bit more searching within this thread. I hope to make some minor additions to the Wiki that you wrote at some stage.

Edit:
So I forgot to ask, does OMVoiceServer need to be started manually before Ovi Maps is launched, or is it meant to be started in the background when Ovi Maps is launched?