Any music scheduling software should usually output their plans as playlist files.
Simply import the playlist file into SAM/add it to the queue and SAM will automatically add the files specified inside the playlist file.
If you need to flag the tracks correctly as IDs/sweepers etc. you'll have to import/reflag them by hand I think. Unless of course the scheduling software is aware of SAM's database structure and credentials, then it could automatically add the files to SAM for you.
By default if you import a playlist (m3u/pls/asx) into SAM and SAM does have a track from that playlist in its own library, it will use that information in it's reports.
If SAM does not know a file from a playlist (m3u/pls/asx), it will automatically add it as a type S track, but not put it into any of it's categories. You'll only be able to find said track using the search of the Music (All) "meta"-category.
As SAM doesn't know or even consider different track types from playlist files, it will not report a file as Station ID/Sweeper in it's royalty reports if that's what you care about. (Other than these and possibly the option of using the tracks in SAM standalone mode without prescheduled content I can't see any reason why you would care about how the song types are reported inside SAM)