Found this lone snippet on the Autodesk site...
Error when opening Autodesk® Land Desktop 2004 drawings in Autodesk Land Desktop 3
Published date: 2003-05-14
ID: TS80350
Applies to:
AutoCAD® 2004
Autodesk® Land Desktop 2004
Autodesk® Land Desktop 3
Issue
You saved an Autodesk® Land Desktop 2004 drawing to an AutoCAD® 2000 drawing format from AutoCAD 2000. When you open the drawing in Autodesk Land Desktop 3, the following error message is displayed:
ARX_ERROR: eNotThatKindOfClass
Unable to find or create project path <c:\land projects 3x:d\alignPress any key to continue... *Cancel*
Solution
When you open an AutoCAD 2000 format drawing that contains Autodesk Land Desktop 2004 objects in Autodesk Land Desktop 3, you will be informed that the drawing should be saved as R14. However, this will not prevent the errors from occurring again.
To correctly share drawings from Autodesk Land Desktop 2004 with earlier versions, you should use the Export to AutoCAD command in Autodesk Land Desktop 2004. You will be able to save the drawing in version 2000 format which can be used in Autodesk Land Desktop 3.
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