i updated the plugin and now i have on the header of admin panel:
Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at xxx/wp-content/plugins/wpallimport/controllers/admin/import.php:1) in xxx/wp-content/plugins/wpallimport/controllers/admin/import.php on line 16
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at xxx/wp-content/plugins/wpallimport/controllers/admin/import.php:1) in xxx/wp-content/plugins/wpallimport/controllers/admin/import.php on line 16
besides, the importer resets the process at some point and when i try to continue, it starts another new import document apart from the original. but first, i gotta figure out the above problem.