There is a "final topic" when I can read and then move all the 1.4 data, to 1.6 or 1.7 (it's stable?)?
No... as far as I know there is no topic about moving data from a 1.4 to 1.6 database. All of the tables are different. 1.6 also has a fourth table for settings... with 23 settings in it.
Do you have a lot of critical-value data that must be transferred? If so... like how many articles?
Can you provide a link to your domain so I can have a look at what you have there?