Here's a quick script I wrote to write multiple input files for crystal14 from a list of refcodes. The script reads a .txt. file (which can be changed to a gcd file if necessary) and writes out .d12 input files for crystal14.
I used this script to write input files for about 240 calculations, all using the same method. Obviously you'll need to change the script depending on what you require from your calculations. See the manual - http://www.crystal.unito.it/Manuals/crystal14.pdf
It definitely could be written in a better way, but it's just an example.