Alias UGS NX DirectConnect is a stand-alone utility that allows the exchange of 3D model data between Alias and UGS NX.
In the Construction Settings window:
Set tolerances as follows:
 since this tool creates
                     multiknots in Alias geometry.
  since this tool creates
                     multiknots in Alias geometry. 
                   between trimmed surface
                     boundaries, since excessive amounts of data are created in the resulting
                     surface. If Skin is used between trim boundaries,
                     check the resulting surfaces for multiknots before export.
  between trimmed surface
                     boundaries, since excessive amounts of data are created in the resulting
                     surface. If Skin is used between trim boundaries,
                     check the resulting surfaces for multiknots before export.
                   and Surfaces > Swept Surfaces > Rail Surface
  and Surfaces > Swept Surfaces > Rail Surface   to ensure and control curvature
                     continuity between surfaces.
  to ensure and control curvature
                     continuity between surfaces.
                  Before transferring geometry between Alias and UGS NX, consider the purpose of the transfer to plan an appropriate workflow.
Two common workflows are:
There are many variations on these two examples. Whatever the transfer scenario, carefully plan the transfer process, to ensure that the appropriate data is written out and is useful.