Can't get model to load

[Blue]

I followed Neil's blog entry about creating your own model.  I have all the requisite files, like the original obj and mtl files, the utf8 files, entity_metadata.json, javascript and text files, however the model will not load from the web page.  I can load the cow model, but when I swap in my values in models.js, the web page is stuck at "Loading...".  I tried stepping through javascript code using Chrome Developer Tools, but haven't been able to determine where it is getting hung up.  There is a good chance there is a mismatch in the number and names of layers I entered while running part_grouping.py, since I didn't know what I was doing.  But how can I troubleshoot where the problem is?  In the javascript code, the function "onModelLoad_" is never hit.