Google spreadsheet live Data

First of all, i love this plugin!
I’ve managed to import all data with the syntax =IMPORTDATA("http://www.mywebsite.com/wp-admin/admin-ajax.php?action=cfdb-login&cfdb-action=cfdb-export&form=.....

Sadly i didn’t have the same luck with the =cfdbdata("http: syntax, mandatory for the long string (i want to split data in different sheets)

I’ve copied the script as it was, and filled the formula with my credentials (in a different spreadsheet than the above one) but i got an error.

The difference between the guide is that it refers to “>script editor>choose spreadsheet”, but i have, in italian, “add on for google sheets” and “custom functions in sheets”.

I’ve tried both, with no luck.
I’ve tried to run the code of the script, and the cfdbdata runs after i authorize it to connect to an external source..

Other functions return errors..( SyntaxError: Empty JSON string (riga 79, file “Codice”)) and so on..

Any ideas?

https://wordpress.org/plugins/contact-form-7-to-database-extension/