how enable Security Grups in custom modules from SugarCRM 6.5

Hello everyone, first one sorry for my english, is not my first lang.

I have recently migrated a SuiteCRM 7.6.6 from SugarCRM 6.5 and works fine except by some custom modules made in SugarCRM. In this case this modules can’t be used the security groups.

I try to follow this instructive, (page 12) but still don’t working! I have the following error:

Fatal error: Call to a member function add() on null in …/modules/AOW_Actions/actions/actionCreateRecord.php on line 360