Assuming those web objects arent the issue, then the Developer Console messages are telling me that the JS is failing to find necessary data. So, the next place I would look is the XML data itself. Check that every one of your JS var sets on each slide are definitely correct.
I believe you may have got one of the JS variables incorrectly set - maybe accessing the wrong level/node/child from the XML?
Without being able to see the XML its impossible for me to know for sure, but I would manually trace out to the console each JS variable after setting it from the XML, that will tell you for sure if its set correctly.
Good luck! :)