When attempting to clone source for mojoPortal project through TortoiseHG get the following:

% hg clone --rev 0 --verbose -- https://hg.codeplex.com/mojoportal .
adding changesets
adding manifests
adding file changes
transaction abort!
rollback failed - please run hg recover

I am right clicking an emply folder locally, then taking TortoiseHG>clone, and am using https://hg.codeplex.com/mojoportal for source.
I have been trying to clone to revision 0, and followed other instructions/recommendations on mojoPortal site and still get the above error. Please advise. Thanks, Dan.