I'm also able to successfully install the repository from my local tool shed to my local galaxy instance, but see some problems - here is the relevant section of the paster log. It looks like most of the problems are due to the way you are importing modules into your mofFiles.py modules. Keep in mind that anything you import must be found in the environment in which your repository is installed. I don't have pybel available in my environment, so the molFiles module won't properly load and also none of the proprietary datatypes are loadable.
galaxy.web.controllers.admin_toolshed DEBUG 2012-05-29 15:05:30,173 Loading new tool panel section: gruning
galaxy.util.shed_util DEBUG 2012-05-29 15:05:30,888 Adding new row (or updating an existing row) for repository 'gruning' in the tool_shed_repository table.
galaxy.datatypes.registry DEBUG 2012-05-29 15:05:31,573 Loading datatypes from /Users/gvk/workspaces_2008/central_051111/database/tmp/tmpFpn0k6
galaxy.datatypes.registry DEBUG 2012-05-29 15:05:31,623 Exception importing proprietary code file /Users/gvk/workspaces_2008/shed_tools/gvk.bx.psu.edu/repos/test/gruning/178caf3f76c0/gruning/datatypes/molFiles: No module named pybel
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,624 Error loading datatype with extension 'mol': 'module' object has no attribute 'molFiles'
galaxy.datatypes.registry DEBUG 2012-05-29 15:05:31,625 Exception importing proprietary code file /Users/gvk/workspaces_2008/shed_tools/gvk.bx.psu.edu/repos/test/gruning/178caf3f76c0/gruning/datatypes/molFiles: No module named pybel
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,625 Error loading datatype with extension 'mol2': 'module' object has no attribute 'molFiles'
galaxy.datatypes.registry DEBUG 2012-05-29 15:05:31,626 Exception importing proprietary code file /Users/gvk/workspaces_2008/shed_tools/gvk.bx.psu.edu/repos/test/gruning/178caf3f76c0/gruning/datatypes/molFiles: No module named pybel
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,627 Error loading datatype with extension 'inchi': 'module' object has no attribute 'molFiles'
galaxy.datatypes.registry DEBUG 2012-05-29 15:05:31,628 Exception importing proprietary code file /Users/gvk/workspaces_2008/shed_tools/gvk.bx.psu.edu/repos/test/gruning/178caf3f76c0/gruning/datatypes/molFiles: No module named pybel
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,628 Error loading datatype with extension 'smi': 'module' object has no attribute 'molFiles'
galaxy.datatypes.registry DEBUG 2012-05-29 15:05:31,629 Exception importing proprietary code file /Users/gvk/workspaces_2008/shed_tools/gvk.bx.psu.edu/repos/test/gruning/178caf3f76c0/gruning/datatypes/molFiles: No module named pybel
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,629 Error loading datatype with extension 'sdf': 'module' object has no attribute 'molFiles'
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,629 Error appending sniffer for datatype 'galaxy.datatypes.molFiles:SDF' to sniff_order: No module named molFiles
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,629 Error appending sniffer for datatype 'galaxy.datatypes.molFiles:MOL2' to sniff_order: No module named molFiles
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,629 Error appending sniffer for datatype 'galaxy.datatypes.molFiles:InChI' to sniff_order: No module named molFiles
galaxy.datatypes.registry WARNING 2012-05-29 15:05:31,630 Error appending sniffer for datatype 'galaxy.datatypes.molFiles:SMILES' to sniff_order: No module named molFiles
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In any case, I'm still not able to produce the behavior you've logged below, and my line numbers for certain method calls are different from yours. For example, your