Thread:Extension talk:Access Control Panel/Help in the privilegie management/reply

Very sorry for not noticing your post earlier. What matters is that the titles of your pages for which you want to control access are prefixed with the namespace ID. So suppose you have groups A and B, then your pages in group A should have page titles like "A:Page1", "A:Page2", etc. (replace the "Page1", "Page2" bits with your actual page titles, but make sure to keep the "A:" in place). The users in group B will then not be able to access these pages (assuming that your definition was that only group A has access to the pages of group A, or to be more precise, to the pages belonging to namespace A). See the updated documentation of this extension for more information.