Just use the existing one.
After starting Creo 7, open the configuration editor and see if any of the settings have a red flag, indicating they are no longer valid.
You can copy the config file from Creo 4.0 and use in Creo 7.0 by placing that in start in directory of Creo 7.0
Thanks.
I would suggest you download the config options and compare them yourself so you can see if there are any new ones you want to add or if there are any that have been deleted.
Creo 4 configs:
Creo 7 configs:
Alternatively you can use Oalf's site: