Right, there was quite a lot of information in there. Clearly you are using some form of Windows on your PC but at least you are using the command line form of scp and sftp. Furthermore it is Sftp not plain old unsafe ftp. I'm going to make an assumption here - I hope that winscp supports the same command line switches and syntax as scp itself does. Both scp and sftp are layered on top of the secure shell (ssh) protocols and so I'll start with them.
When ssh connects it needs to do two things: (1) ensure the machine it is talking to is the machine you want to talk to, and (2) prove to the remote machine that you are who you claim to be. Clearly step (1) is happening OK at the moment, so let's ignore it. In a nutshell ssh has to identify you (username) and authorise you (possibly by a password). Both of these are initially under the control of the client (your) machine. Lets start with a simple login:
$ ssh vitalbox
The client sends information to the server (vitalbox) including your username. If instead you use:
$ ssh kris@vitalbox
you will attempt to log in as Kris.
He won't like it, so don't actually try. If though, instead of kris, you used the username "nobody", then as far as the server is concerned you ARE "nobody", you own the files and can do what you like with them.
The next step is authorisation. ssh can use a number of mechanisms to authenticate users, the most common being a password or public key cryptography (PKC). If I was the admin of the server I'd be unlikely to let you have the password to the "nobody" account, but I might consider allowing a PKC connection. You need to create a pair of keys (you may have already done this) one of the pair is the private key and the other the public key. Kris will need to add your public key to the ~/.ssh/authorized_keys file in "nobody"'s account on the server. The following then occurs:
1) Your client sends a message both in plain text and encrypted with your private key.
2) The server decodes the encrypted message using your public key (which it already has).
3) If the two match then you must have been the sender.
Right, so much for the theory. What it means in practice is that you should be able to perform commands such as:
$ scp myfile.txt nobody@vitalbox:pages/mywiki/
Assuming that
pages/mywiki is a subdirectory of "nobody"'s home directory. Talk to your server admin, you will need him to agree and to cooperate in setting it up.
HTH.
MartinR (MartinRhome is an alternative account I had to use because I lost track of my work account's password)