When you import a Station, Offset, Elevation file you get two choices if you use the import command rather than drag and drop - the settings at the base of the import Dialog give you the choice to
1) import as stored cross sections - in this case the file imports, builds stored cross sections and then creates a surface from the sections - the surface can be deleted if you don't need it
2) import as Points - in this case the file imports, creates Points and joins together points of same code (or maybe you have to process feature codes to do that (sorry I cannot recall if that is automatic or not) and then it will also build a surface - again you can delete the surface if you don't need it.
On point import - you can tell TBC whether your file has point IDs or not (iD, Station, Offset, Elevation, Description) or (Station, Offset, Elevation, Description)
If you drag and drop a file into TBC you do not get these options and it uses either the default or last used settings from a previous operation.
In v5.1 you will also be able to pick the alignment with which the points or sections should be associated with - currently the file name needs to match the alignment name if you have more than one alignment in the project - if there is only one alignment then the data gets associated automatically
Points or sections get placed on a layer of the same name as the imported file (I think that is the case - it is with XSR or GEN files at least
Hope this helps
Alan
Sent from my iPhone