Importing the Lines
1. Digitize the model and save the ".obj" file the way you normally would.
2. Import the file into Alias.
You will need to use the Alias file browser to locate the file in the file system. Once the file is loaded into Alias, you can open up the windows by using "alt-w" to view the wireframe.
3. Convert the Lines into B-Splines.
Pick -> Object to select the lines in the file. When all of the lines are highlighted, use Object Edit -> Fit B-Spline to create splines where the original digitized lines were.
It would be a good idea to pick the digitized lines again and save them for reference by using Oject Display -> Tgl Template.