yes, there's a current issue with the way that's read - it _can_ be fixed in the style, but it shouldn't have to be, since the style follows csl standards (and it affects almost every style):

Frank - here's the issue:
<names variable="editor translator" delimiter=". ">
<name and="symbol" delimiter=", " />
</names>
The current processor (or is it Zotero) doesn't read this correctly and just prints editor, not translator (even in cases where there is no editor). Could you check this?

euj - if you're in a hurry I can tell you how to hack the style to get around this, but I really hope we'll get this fixed in Zotero asap.

change the macro editor translator to this
<macro name="editor-translator">
<group delimiter=". ">
<names variable="editor translator" delimiter=". ">
<label form="verb-short" text-case="capitalize-first" suffix=". " />
<name and="symbol" delimiter=", " />
</names>
<names variable="translator" delimiter=". ">
<label form="verb-short" text-case="capitalize-first" suffix=". " />
<name and="symbol" delimiter=", " />
</names>
</group>
</macro>

http://www.zotero.org/support/csl_simple_edits
for general instructions.

actually, so that this doesn't break with feature fixes, I recommend changing it to
<macro name="editor-translator">
<group delimiter=". ">
<names variable="editor" delimiter=". ">
<label form="verb-short" text-case="capitalize-first" suffix=". " />
<name and="symbol" delimiter=", " />
</names>
<names variable="translator" delimiter=". ">
<label form="verb-short" text-case="capitalize-first" suffix=". " />
<name and="symbol" delimiter=", " />
</names>
</group>
</macro>

i.e. removing the translator from the first <names> line in my code snippet above. Right now this won't make a difference, but once this is fixed globally, the first code will print translator twice, this one will remain correct.

nope.
<names variable="editor translator" delimiter=". ">
is indistinguishable from
<names variable="editor">
in what it displays:
The translator isn't shown, neither if there is only an author and a translator nor if there is an author, an editor, and a translator (with all three being different). In short - there is no way to ever get the translator to show up. This is not just the case for MLA, there were earlier reports about this for APA as well. I hacked that style on the repository because I thought csl specs had changed, but then Rintze pointed out to me that they haven't.

In the test suite of the latest (still unreleased) processor code, this is working correctly, if it hasn't been fixed already.