It's better to copy files. Imagine what will happen if everyone deletes the blockchain simultaneously.

Ok, I'll update the guide.
So copying the .bak versions is the proper way?
No. U must copy *.nxt files. Use *.bak only if *.nxt corrupted.
Ok, I am just trying to set up a simple guide for users who can't operate in linux at all, so too many options would look too complicated.
One observation.
I downloaded a fresh version of NXT to my home PC, installed with default settings, blockchain synced from 0, all good.
But Active peers tab shows only 14 nodes. Is that not too low? Is the reason - the hallmark protection?