You can download the Nericon garden key, which should work for the graveyard.
Lost Items - guide and directory of inventory files

Or, you can bypass the gate;
Teleporting Anywhere, via hex editor


If you install the v1.34 patch (web site still says v1.33 {should be updated tomorrow}, but the download is v1.34) and re-load a save (if you still have one) from v1.32, you should not run into the black map bug again.