The commands FileZilla displays in its console are not actual SFTP commands. In fact, the SFTP protocol doesn't really have commands as such at all, but instead uses parameterized messages with names like SSH_FXP_OPEN, SSH_FXP_READ and SSH_FXP_SETSTAT. The commands that are used in SFTP command-line clients and that you see in FileZilla are only meaningful within the client itself and are not actually sent over the line.
When FileZilla displays chmtime, I think it's simply telling you that it's set the mod-time of the remote file. To do this in SecureFTPConnection, you need to call the SetLastWriteTime method.
- Hans (EnterpriseDT)