From Jay:
The download post for the Developer Map Editor Hack gives a lot of information: http://www.ztcdd.org/DG/index.php?topic=5356.0
One thing it says: "The Developer Map Editor does not allow placing food because ZT would not actually use those objects as food."
ZT would not actually use food placed by the Zoo Admin map editor either. That is built into the ZT program itself rather than part of configuration. APExp 3.2 allows creating decorative scenery pieces using ZT's various hay and meat graphics, but those would just be scenery and not food that animals would use.
The download post also says: "For developerMapEditorHack.ztd, it should not be in any ZT folder (although it could be in a mapmaker-unused folder) at the same time that the Zoo Admin map editor is in a ZT folder."
The download post also has a section saying "Where To Put The ztd".