Conversations inbox could do with some sort of folder for message storage I have searched but there dose not seam to be any addons that do this. This has been requested by one of my admins to keep certain info for repeated use.
Furthermore I'm not sure I understand the requirement for "some sort of folder for message storage" as all your messages are there, and filterable. There is also an additional filter you can use which involves putting a "Star" next to your favourite or important conversations.
Your thread is titled "Conversations Inbox" but that already exists: Yep I know I titled it because that's what my post is about, the "inbox and its contents and the ordering & storage of the contents like a folder system similar to what you could do in VB PM's.
Thank you for sharing the stars filter, we are new so there's a lot to take on board and it is all to easy when your new to a product to miss things that others may think is obvious.