2b. If you have attached documents in 1Password, you need to manually add those to Bitwaren.
This process is pretty straight-forward, though. To get a clean list of all items with file attachments in 1Password, I found it very useful to create a Smart Folder with the rule "Number of attachments is greater than: 0".
I have several entries in all of these types. Of course, you can map them to one of Bitwarden's types (usually as a Login, I would guess), but as far as I remember, it would have taken quite a bit of manual cleanup to get this to work right. I wonder why Bitwarden doesn't have additional types, even if just as a way to have some better organization of your items.
I will definitely try Bitwarden again in the near future. I recently reverted to 1Password 7 which works so much better than 8, but as EOL for 1Password 7 is imminent and my subscription renews in the summer, I think it's time to try the alternatives again.