To Promote Elements by range

Import a file that contains a simple curve by selecting File > Import.
Select the desired file and click Open.
Open the Node Types dialog and drag the Range node, using the Technique ByLowHighRangePoints to the Graph window. After, input values for the LowPoint and HighPoint that encompass the surface.
This is the range used to select elements to promote.
Select the node BSplineSurface node, using the Technique SelectNodesWithinRange, and drag it to the graph, and give it the required inputs. After, promote it using the Promote Element tool. This technique is used whenever a GC node type is permissible as input for some other node and either a list of nodes is required or the input property is replicatable.
This creates only the BSplineSurface and excludes all the control points.

At this point a new node has been created for the model attachment, the range, and the BSplineSurface. Although the surface cannot be manipulated or deformed in GenerativeComponents, it can be used to reference new nodes. The only way the surface can be deformed is by editing the original attached file, saving the file, and replaying the model attachment transaction. All downstream nodes will update accordingly.