Re: Users editing only their pages
Yes, it is. You have to set the perms. manually to the pages. You could remove global perm of tiki_p_edit_page to that group of users, and allow locally only to their pages (you have to say which are their pages).
Or (more advanced feature), you could (I guess, I'm not sure) use AulaWiki Mod to set workspaces permissions, and let the users create pages only inside that workspace (and the perms being inherited from parent pages). I'm not sure about this, but I'm afraid there is some way to have this behavior with workspaces (see http://edu.tikiwiki.org for for information on aulawiki Mod, howto install, use, etc. if interested in trying)
Hope this helps...
And welcome to Tikiwiki, by the way... 
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