I have been using SharpSVN and love it but I wanted to make sure that the .GetLogs() and .Diff() functions in no way actually edit data on the repositories. These things just get you the information stored in the logs as if you were repo-browsing and looking at the logs through something like TurtoiseSVN right? Thanks.
I believe your assumption is correct. However, to test this you could access your repository using read-only credentials (how you set this up depends on your server type), and if everything succeeds then you aren't trying to modify your repository.