You don't really need that precisely customization and I will tell you why:
Take a look into some customization files and you will notice some resemblances meaning that:
Header is almost the same, so keep one form another customization file.
What makes the difference for a particular FS is
<allowed-language> …… </allowed-language>
There are a few rows that you need to match with your present FS in order to have all those languages on your phone.
Second important thing are the certificates. Again as you will see they are basically the same as for every phone, so you can copy those lines form another customization and also the certificate files.
Now, all the remaining lines in the customization can be removed without worrying, those lines are only for the purpose to make some settings in the phone, as you would by accessing phone’s menu. Also some lines have the single purpose to disable things like flash desktop, wireless willage and other things…