Getting familiar with your amazing project and have faced with such issue - can not enumerate DAO recordset fields - unable to cast from Field2 to Field. Looked at the code and tried to fix by replacing Field with the base _Field which should work with both Field and Field2 - and it seems to work. For now I've checked only with Office 2013 and 2016/365, going to check later also for 2007 - that's the lowest version I need to support.
Attaching svn patch as text - may be it would be helpful.
Fields.patch.txt
This is based on feature request from https://github.com/NetOfficeFw/NetOffice/issues/19
Original request: