Hi Rogerio,
For documentation on the Word Object Model you will need to look at the VBA Docs on it:-
msdn.microsoft.com/.../ff837519.aspx
Unfortunately It is a large and complex API.
excel.if and word.if were files for using OO Vocabularies. We would advise against using them as they would be very out of date from any recent Word version. They allowed you to use a slightly different syntax. The code you supplied did not rely on a vocabulary so its best to leave commented out.
Regards
David