ModWest documents CVS setup here. That works fine. They also tell you how to authenticate via public/private keypairs
here, but I was not able (so far) to get that to work.
No worries: I was able to use the latest TortoiseCVS to do a checkin, getting a lot of extra messsages and having to type my password a few times - nothing backbreaking for the current time. Settings are: :ext:snrygaard@shell.modest.com:/cvs