If I select an item in the marketplace, select a character to have the order sent to other than my "main" (trying to send it to Ashlait), and then add an augment, when I submit the order it's marked to be sent to my "main" (Tetharel--who's not so much my main in Rift, but was in WAR, back when I joined). Submitting the order without using the "customize" button lets me correctly specify having it sent to any character, as expected.
No big deal (I can just in-game mail it where I want it), but I thought you might like to add it to the ever-expanding to-do list. :-)