Hi
Custom.css file will not be affected when template is updated , regarding copy the custom work , yes you can override the style code in custom.css file ,
But I am afraid I do not give u the path of your changes since it personal custom work did by you .
Ok .. well .. so i have to take a backup of my modified css files. Then i replace them with the original unmodified files. Finally i have to manually compare my file with the original file to extract my custom work.
This will take some time but it is manageable.
