This goes to other new Map Makers who want more in their map! 
I am using T4M mod so I'm unsure if this is why I have so many .ff's allowed BUT even still its cool! can anyone Confirm?

so far heres what I personally use 

localized_patch.ff
localized_common.ff
localized_Plunge.ff (Normally Plunge is your map name ex: localized_nazi_zombie_MAPNAME.ff)
Plunge_patch.ff (Normally Plunge is your map name ex: nazi_zombie_MAPNAME_patch.ff)

I also think there are more but I can't confirm at this time. if anyone else can verify that'd be lovely!   
I have done searches but found no record of a list like this or anything like it ftm!

Thanks again!