I tried just_to_helps method to MAC change and now my N810 won't even boot.
The Nokia text with white background only stays on when booting. Reason for that might be that MAC-code script is not working in rcS-file or something.
Hopefully I get my device work with reflashing. Will it work to replace the rcS-file to working one or what I suppose to do?

EDIT: I reflashed the software and now it's booting.