The "over speed limit" is down purely to Destinator. As far as I know, it's not configurable.
To get the touchscreen, open the C:\PowerLOC\Destinator\Common\Interface\Destinator .inf file and change the line
(the first two sets of numbers might not be right, but it's the last one that's important) Change the last number to at least 640, or change it to your screen width for it to appear in the middle.
With voice...that is a common thing with Destinator SDK, missing things out, just saying "Yards" or "Right turn, yards" without a value ;)