1228
issue 1.
portal uses api of crm to login user
soap/customerportal.php
Currenty you have hook on user save modules/Contacts/ContactsHandler.php
"portal" field of customer on frontend is
If somebody removes " || 1==1" condition from Contacts_sendCustomerPortalLoginDetails function, you will be able to prevent login attempts from finding it
alternative way is just delete such records (set deleted flag to 1)
Issue2
We can modify SimplyImport plugin integrate standart importer functionality
Each imported row will be checked for matches and chosen action(skip/modify) will be done instead of creating new record