Hello Rubberduck,
1: http://forum.i-doit.org/index.php/topic,3140.0.html
2: http://forum.i-doit.org/index.php/topic,3141.0.html
3: You should take a look at our report-module (extras > reports)
4: You have several options:
You could add your suppliers as a organisations (in the contacts) and add these as "contact assignment" with the role "supplier"
You could create an own category in the administration area: "Administration > Custom categories".
Best regards
Leo