some loot items end up selected in the bottom center of the screen (thief 3) : what do i do with these ? they look like loot, plates, goblets, etc. ; thanks

If I'm understanding you right, not all dinnerware/etc can be looted. These you can throw to cause a distraction for the guards.

In Deadly Shadows, if it's loot, it glints (with the odd exception: [spoiler link]). If it doesn't glint, it isn't loot, even if it has exactly the same model as some of the loot.

In the first two games, you had to learn that the golden plates are loot but not the silvery ones, and the gold-ish bottles are loot but not the green ones.