The Sims 2 University No Cd

I'm running to make the photos for updating, but I need some help: how to use the OMSP with angles?

http://linna.modthesims.info/download.php?t=317716

Especially these (the others do not give me problems)-Angled Shelves-AL-Shiftable

I try to put the sim (or even an object) over this and actually change the angle, but the air! I would like to put a right angle to the ground changed and instead I see it floating.
Well, I do not know what to do ^^'''

A big thank you in advance! Nothing