You want these armors inside chests as loot?
There are two ways to do this...
To add to level lists...(The armor will have a 'chance' to spawn, like other armors etc)
Go into the Leveled Items tab on the left, you'll find it under Items.
Scroll down until you find entries beginning with LL0LootArmor. (They will end with Oricish, Mithril etc, based on what type of armor they hold.)
Place your armor in those lists, based on where you think it would be most appropriate.
You can even create your own list, if your armor doesn't really fit into any of those existing lists and then add your new list to one of the LL1LootArmor lists (Some end with Heavy, Magic, Light etc, depending on what they are and the number at the end, like 90, 75, 25, is the % chance they have of spawning. 10 = 10% chance to spawn etc.)
To add directly to containers... (The armor will always spawn in that chest)
Go into the Container tab on the left, you'll find it under World Objects
Now scroll down unti you find the entries beginning with Dung (for Dungeon), like DungBanditChest1 etc.
You can then add your armor to the chests
Have a mess around with the lists and try to understand them first. Then you'll get better results. You can right click on a list and click Use Info to see what other lists contain that list/item.