[Zope] security setting question

[Webmaster Expert RH]

Hello zopers,

I have a situation like this :

A repository filled with custom class instances ie: DATA folder( w/
Catalog)
A script that catch and sort a Catalog Query (get-selection)
A dtml-doc that show the results from the script <dtml-in
get-selection()>

What I want is user w/ a specific role ie : custom_user
To be able to :
- create new instances
- view and edit only those instances THEY have created

Please can you point me any path to reach this goal ?

It must have to do with the skip-unauthorized and special setting of the
security tab (but wich ? The repository ? The script ? The dtml ?....)

Thanx in advance.