I've been using directory opus to connect to our servers using SSH for a while now using a username and password. We have now changed over to using a private/public key to connect via SSH to the servers and need to type in a passphrase instead of password to connect. I can't find a way for dopus to ask me for a passphrase instead of a password, is there anyway to for me to
Yes, via Pageant which is part of PuTTY.
See here for some more details: [SFTP login with rsa-key)
Using Pageant works 
If I put a space for the password in the FTP settings it doesn't even prompt for a password when it connects.
The downside though is that I have to type in all the passphrases everytime windows boots up so that they get cached in Pageant. This isn't ideal and it would be nice if I opus supported passphrases so I could just type it in when needed.
Thanks for the info
Good idea putting a space as the password. I never thought of that, and it makes things much smoother. I should write this SSH stuff up into a FAQ. (Edit: Done)
I guess Pageant doesn't let you cache the passphrases for security reasons. You could automate typing them in using something like Keepass (where you'd still have to type one password to unlock the password database and could then hit the Ctrl-Alt-A hotkey to auto-type each passphrase) or one of the keyboard/mouse automation tools (where you wouldn't have to type anything).