[cvsnt] How to undo?

[kopi at scanita.net]

I just started to use CVS, but unfortuanely I have nobody to talk about it. I
use Tortoise CVS together with CVSNT. I know that Tortoise CVS contains CVSNT,
or at least cvs.exe, but I installed both. Did I? Gosh, I'm still confused
about that. I do have the CVSNT 'service panel', so I guess I have installed
CVSNT separately...

Now that have already build up a repository, I wonder how I could undo mistakes
like adding a module into the wrong location inside the hirarchy of the
repository. Is it okay to simply delete () the corresponding folder inside the
repository and add it again? Furthermore, could I damage the repository in any
way if I delete a sandbox? Generally, how to undo an add, commit, etc.?

Thanks for any help.

-Sacha