How nested group works

I'm going crazy with this problem. Here is another example, i followed your indication and here is what i get:

Note: Comando top doesn't have any nested group and have Level 3

[attachment=2:mp1kbpu3]<!-- ia2 -->Clipboard01.gif<!-- ia2 -->[/attachment:mp1kbpu3]
[attachment=1:mp1kbpu3]<!-- ia1 -->Clipboard02.gif<!-- ia1 -->[/attachment:mp1kbpu3]
[attachment=0:mp1kbpu3]<!-- ia0 -->Clipboard03.gif<!-- ia0 -->[/attachment:mp1kbpu3]

It difficult to see because your screenshot are partial
But it seem that commando top is nested in all other groups.
Thus it herits from the permission of all other groups.
Emmanuel.

But Comando Top it's the main group, should not all others group be nested to this?

From your first example, this is what i understand:

EBU Users - Nested group: EBU editors - Level 3 - subgroups similar with Telesales groups
EBU editors - Nested groups: none - Level 4 - Top group, similar with Comando Top

I think you make a confusion between children and parents. In FLEXIaccess you set the children of a group.
A child as MORE permission than his parent.
In all other components you set the parent.
Think about the standard Joomla groups:
Administrator and Super Administrator. If you wish to replicate this in FLEXIaccess you should do the following settings:
1) Administrator - level n - Nested groups(children): Super Administrator
2) Super Administrator - level n+1 - Nested groups(children): none

Cheers,
Emmanuel.

Emmanuel, please tell me, following settings are correct?

comando top - level 3 - nested group:none
comando ts brasov - level 2: nested group: comando top
comando ts bucuresti - level 2: nested group: comando top
...(other more 5 subgroups)

If yes, then i have a problem because i'm logged in as comando top user and i see 7 links instead of one

In the structure you show me commando top (which is nested in every other group) inherits the permissions of all other groups.
Thus commando top can see all the links the other can see.
If commando top must have LESS permission and see LESS links than the other group, your structure must be reversed.
Cheers,
Emmanuel.