new account preference customizations

[fedora]

I would like certain default preferences created upon accout creation as 
well. I figure most of these will go under /etc/skell but I am not sure. 

For example, Mozilla default behavior preferences. Looking in my test 
account I see in .mozilla/default/*.slt directory. As this number seems 
random upon creation I am assuming the extension .slt is the 'salt'? If so 
how does one properly create this directory so I can recreate it from a 
template with an updated prefs.js and bookmark.html file?



Another example would be creating some extra Gnome menu links and items on 
the lower screen menu pane. Like adding Adobe to the Fedora->Office area 
and adding a Terminal icon to the bottom menu pane.


Thanks

Greg