You can import a boundary file to be used for finding and clipping elevation data. Here are the steps:

1. Export a DXF polyline file with only 1 feature (boundary)
2. Copy DXF to your Z-Tools project – put in DXF folder
3. Open the Tools…-Manage Layers (XML) tool
4. Import DXF Button
5. Fill out info on import tool
   1. Browse to DXF folder
   2. Set the DXF projection
   3. Get Files and check the DXF file
   4. Process (this should create a boundary XML file)
   5. Close Manager Layers
6. From the Map – use the Layer button to pick the new boundary