Hi,
welcome @forums.autodesk.com !
If you have the same problem with both releases, 2013 and 2014, I guess the source might be then your drawing.
Have you tried to create a field in a new drawing (based on an original AutoCAD template)?
And what is exactly the position when AutoCAD crashes, when starting the command, placing the insertion point, select a field type in the dialog, ...?
- alfred -