Hello Rama,
It is unclear if you use AC standard (ACS) or AC classic version (v6/v7) because you give one documentation link for each version.
On ACS I think you can only save the fields values in the default Profile table (recipient).
On AC v7/v7, take care, there are 2 webApp activities (Page and Page v5 compatibility).
With the default one, you can choose the Document type (by default, it is nms:recipient); so if needed you can choose another schema, such as nms:visitor, or your own custom data profile schema, and even other custom schema for storing other type of data than profiles data.
Regards.
Jean-Serge