[TYPO3-english] categorization and permissions

[MantasK]

Hi,

I want to have such configuration:
country1
--category1
--category2
country2
--category1
--category2
etc..

I need this configuration because I want to handle user permissions. 
Basically a user can edit only one country.
I've created this structure with sysfolders I've also configured tca and 
everything is working, but now I'm not satisfied how record lists are 
shown in sysfoldier.
I have an idea to create a back end module for displaying these records. 
My questions is if I create that module, how can I handle permissions 
and categorize content in the way I've described above? If I create a 
module which returns a list, can I select to display that list in 
specified sysfolder? If yes I think I can write some TSconfig so that 
module could now how to filter information. And what type of module I 
have to create to handle this.
Do you have some ideas?

Thank you
Mantas