Transmutation transfer problem

warlicker84

I've been having issues with the Jubilee Event armor pieces. I cannot transmutate an item more than once. Example Transmutate appearance of the Cerimonial Armor on a blue Plate Armor +1, then when I try to change the appearance of another armor piece, the system won't let me put the changed Plate Armor piece in the "Change Armor Piece" slot. Here is a pic of what is happening to me.
imgur.com/iXGd4Vi How can I transfer Armor Appearance across multiple items with having a store of extras?