Alias 2011 and Alias 2010: wirefile compatibility
Some changes have been made to the wire file structure in Alias 2011 that may result in some data not being imported correctly in Alias 2010.
In Alias 2011, the Curve Edit > Fit Curve tool uses a new fitting method, which gives much better results than the previous algorithm. As a side-effect, construction history on curves that were fitted with this tool in Alias 2010 will be lost when those curves are imported into Alias 2011.
The new Cross Section Editor in Alias 2011 lets you create two types of visual cross section groups that were not available in Alias 2010: Axis Discrete and Planar.
When loaded into Alias 2010, these new cross section groups will load as Picked Reference groups. They will contain the same section planes as in 2011, but will not be editable.
Creating free curves by projection
In Alias 2011, projecting a curve onto a surface with Surface Edit > Create CurvesOnSurface > Project to create a free curve (Create option set to Curve), when Match original is not on, uses a completely different algorithm than in 2010.
If you project a curve in Alias 2010, using the Curves option and Match original off, without modifying the Degree or Max. spans, then loading the curve into Alias 2011 will cause it to be rebuilt with 100 spans when its construction history updates.
