Warning - could not install some modules: S1TBX Feature Extraction Tools - The module named org.esa.snap.snap.raster was needed and not found. 2 further modules could not be installed due to the above problems.
This could either be caused by a temporary server issue or your local SNAP installation is corrupted.
Could you tell a bit more about your SNAP. Which version have you installed? Have you tried to update SNAP or was your intention to add the S1TBX to an existing SNAP installation?