The Amulet of Istara and the Armor and Scale Tech Kit: Ethereal Essence Salve both explicitly state they can be applied to any armor piece. However, when I tried to apply them to my new steelsilk cargo leggings (only tech'd with Armor V and Power V), they would not apply. I tried applying the salve also while equipped with the leggings; it did not apply, and the error message I got was "You do not meet the requirements to use this item." What kind of requirements are there to using the salve? I'm a master craftsman. Is it that my adventure rating is only 149?

Please help me to use the quest rewards as the description indicates they should be used?