Hello,
Unfortunately, there is no such script. However, we can write it for you. It will be executed in a Business Rule triggering After creating a user and append the necessary data into the CSV file. If the solution meets your needs, please, provide us with a sample of the CSV file, clarify the LDAP names of user attributes whose values should be appended to the file and the corresponding column names where the values should be added. Then we will provide you with the script and detailed instructions.
For your information, if you have multiple instances of Adaxes service that share common configuration, the file should be stored in a network share folder. This way, each instance of Adaxes service will be able to write updates into the same file instead of into the separate local ones.