After 14 months of frustration my Starlock is properly guiding now !!!
I'm based in Australia, so Southern Hemisphere.
During the past months, Meade has replaced my Starlock, exchaged dozens of mails without success to make it work, it was not even locking at a star...
A couple of weeks ago I spent 5 hours on a 'live' night session (time difference with Australia helped) with two Meade engineers via Skype and TeamViewer; after many tests, Starlock was still not able to guide.
But with all the data collected that night, they'd proposed a very exaustive testing program that I'd carried out the following nights...
Finally we arrived to the conclusion that was a 'firmware' problem link to the Southern Hemisphere, even if GPS was recognizing the correct position in Earth, Starlock was not getting the right commands.
So, the solution is: Reverse L/R and Reverse U/D must be On and Dec, Guiding has not to be in North&South !!!
Now Starlock is locking to a star, completing the ARC Calibration routine and guiding accurately !!!
Last night I took a 15' exposure with round stars for first time.
I'm a happy man now !!!