As Rob said, that's the way you get the material editor, though your original bug reminds me of old issues with MH, that have been addressed with resent builds of MH. Or in short MH 1.1.1 is deprecated.
Just a part of my usual routine of clicking on everything, I went ahead and enabled the Materials Editor plugin. I do not see a tab anywhere though. How do i access it? It seems to be entirely missing. Thanks in advance
Edit: Nevermind, I found it. Under the Utilities Tab, between Logs and Expression Mixer tabs Just another ID ten T error :/