Rewrite vs already rewritten (remove subfolder from URL)

Question

So right now, this is what I've got:

RewriteEngine On
RewriteBase /

RewriteCond %{HTTP_HOST} cpattyn\.uni\.cc
RewriteCond %{REQUEST_URI} !^/ffs/public/ [NC]
RewriteRule ^(.*)$ ffs/public/$1 [L]

RewriteCond %{HTTP_HOST} ztz\.110mb\.com
RewriteRule ^ffs/public/(.*)$ http://cpattyn.uni.cc/$1 [R=301,L]

So this does the following:
-cpattyn.uni.cc/xx loads what's at ztz.110mb.com/ffs/public/xx
-ztz.110mb.com/ffs/public/xx redirects to look like cpattyn.uni.cc/xx
-cpattyn.uni.cc/ffs/public/xx loads what's at ztz.110mb.com/ffs/public/xx (obviously, but I want this changed, read below)

Now I can't figure out how, because I already use it to rewrite and happen to cause a loop with everything I try, I want cpattyn.uni.cc/ffs/public/xx to look like cpattyn.uni.cc/xx (so practically remove the /ffs/public part from the link...)
Does anyone have an idea on how to get this done?