Sorry if this is the wrong forum (or if it's old news for most of you), but I feel I need to warn you about some particular DVDs that will require this aditional step in order to be fully decrypted.
DVDFab or even other softwares like AnyDVD will not decrypt the entire disc alone. So far I have only saw one (perhaps two) titles with this issue, but if you do a Google search you will find people arguing the same "region marking" thing - When Harry Met Sally (confirmed) and Street Fighter/1994 movie (old edition, not 100% confirmed), both from R4/Brazil (note: I owned/have purchased these discs, both were original).
This is the original thread:
And this is the tutorial I translated, based on other one I saw in my language:
After following the procedures above (from the Afterdawn link), I was able to decrypt this disc without seeing the warning "This Player Is Incompatible With Region Marking Of This Disk".