[TYPO3] sr_feuser_register insert in fe_users

[Natalia]

Hi,

Can someone tell in wich file the insert to the fe_users table in the
sr_feuser_register extension is made?
I need to check something and I'm a newbie in typo3... I thought that
the inserts in typo3 where made with exec_INSERTquery but there are only
3 exec_INSERTquery in the extension and none of them seems to insert the
user... Probably I'm wrong.

The thing is that I need to modify a value before inserting a value to
the DB and I'm a bit lost in Typo3 system...

Thank you very much