Radio Shack carries a small contact cleaner with 2 aerosol cans. The product is called DeOxit. You spray the contacts with the cleaner and let them set for a specified time. If there is any oxidation, the contacts will turn black. Brush the contacts off and do the process again, until the contacts no longer turn black.
Next, treat it with the ther aerosol, which is the preventative coating.
If I remember correctly, the kit is under $20.00, and it shoud let you do a few cleanings with the small aerosol cans that come with it.
This kit was developed to keep silver and gold coated contacts clean, without damaging the coating with abrasives.
The spring loaded pins on the bottom of the battery connector seem to be the weak points. The contact mating needs to be near perfect. Doesn't matter how strong the battery is, if these contacts tell the NAZA that the battery is dead, or not present, the NAZA seems to accept the data as valid.
Another area where some error checking would be a welcomed addition. When you tighten up on the sensor routines, there needs to be a watchdog to monitor the integrity of the data.
Since it is a proprietary system, all we can do is guess and second guess, then try to find a mechanical solution to a firmware issue .