I have been recently working with (tearing hair out) Managed Metadata Columns in Visual Studio 2012 for SharePoint 2013.
This site has excellent information on the subject. After deploying the sites example code without error I progressed to make my own column. I generated some GUIDs from guidgenerator.com to use for my new TaxonomyFieldType and Note field elements.
After several days of vague errors and feature activation fails I narrowed the problem down to the field GUIDs. I then replaced the generated GUIDs with GUIDs cut-n-paste from an SharePoint 2013 site (different server) and now my new column deploys without failure! huh?
This doesn't make sense to me but if it helps someone else, so be it.