GPS navigation issues

[#1]

Hello all knowledable SE community..

Trying to use my google maps in car cradle connected to working USB charger I have noticed some issues, wonder if anyone else has same or can comment on these:

* I want the display to stay on not to time-out into stand-by mode for obvious reasons whilst driving. In menu settings->applications->development->stay awake, this option allows to stay awake whilst charging.  This is all fine whilst the x10 is charging but if the battery happens to be at 100% it stops charging and goes into stand-by...   Is there a menu item I'm missing somewhere else that allows me to keep the x10 awake???

*In direction navigation mode - i.e. navigating me to programmed destination with voice guidance function, I notice the battery juice dissappears at a worrying rate.  Even using the original USB lead to keep the thing charging, GPS navigation can eat 10-20% of battery in an hours driving!

Thanks in advance

[#2]

actually using a nokia charger... no issue at all but no hard gps guidance too, just 3 hours trip as much every time so if you are a really hard gps user l will suggest an inverter to connect your wallcharger directly and see what happen with battery drain.