Sorry for maybe dumb question:

I have to update a nüvi 3790 for my friend with CN Russia NT, I have downloaded all the files, updated the files I found on the device, but remains 2 questions: (until now I worked only with outdoor devices)

1. MD2 file goes where and for which purpose?
2. There are 4 downloaded SID files, I did not find any SID on the device, is instant search available on 3790? Which SID I have to copy in which directory?

Thank you in advance for assistance and