BCO QueryByElements doesn't work

Hi all,

I've created a BCO and now I am trying to execute a QueryByElements, but it doesn't work as I expect it to. I've written a simple program in BeforeSave event to debug and put some breakpoints, but program doesn't stop at them, as if the query doesn't execute.

BTW I'm trying to implement a change log following this guide http://scn.sap.com/docs/DOC-60511

What am I doing wrong here?

BR,

Danil