Password Security:
The app never sees the actual login or password (although technically it IS possible to capture that data, however it would be a criminal offense from what I know), but it does stores the authentication cookie with bungie.net to access your characters data. While in theory the author (ie me) could code the app to gain access to your b.net account, it beats me why I would do that and what I'd use it for (dismantle your Gjallarhorn? Complete the Crota HM solo for an unsuspecting user?
. So TL;DR: I can assure you the product is completely safe, otherwise you can find and sue me, heh
Moving an item with nothing else to put into the slot:
Currently, yes, if there's only one item in the bucket, it will fail. I will improve on the algo so it would try to bring something to equip from the vault or another character, but it's a relatively rare case so not a priority right now.
Move to Vault:
Move to vault function will work backwards: you select the char and it will only show items for that character, then you choose what you want and hit a button to move to the vault. So to a certain extent it's what you asked about.
individual character inventory:
There will also be an option to show the location of each item.
