Normally this is done via zmodem but as it seems the package is not installed on the router by default. You could get it via apt-get but I'm guessing no Internet for you since you're working via console.
To get config from the router to PC just cat it to the screen and use copy/paste. To upload use the same, open vi editor, enter insert mode and paste your new config.
If you we're using linux and minicom you could upload file via Alt-S as described here. But with PuTTY the clipboard and copy/paste works best.