Kia ora Maybe I found a minor bug. I have an extended elevation that includes a loop (many actually) and of course there is a gap in the loop as rendered that I would like to illustrate with a map-connection line. Where the yellow shading is in the image below, I would like to draw a horizontal map-connection line. So following the guidance in the Therion Book pages 105 and 106 I have created a scrap. scrap 2-HawkesElevEXT-s1connection -projection extended -station-names []@2 point 0 0 station -name 2.4 -from 2.5 point 100 0 station -name 2.4 -from 2.3 line map-connection 0 0 100 0 endline endscrap On creating the scrap and before referencing it in any maps, Therion is unhappy and exits with the following: #################### end of cavern log file #################### done calculating basic statistics ... done processing extended elevation ... done processing references ... C:\Program Files\Therion\therion.exe: error -- string pointer is null writing xtherion file ... done Am using therion 6.2.0+fd5c1b6 (2024-01-10) On experimenting a little, I realised that -station-names has no effect on the -from station parameter. So this was my workaround. scrap 2-HawkesElevEXT-s1connection -projection extended -station-names []@2 point 0 0 station -name 2.4 -from 2.5@2 point 100 0 station -name 2.4 -from 2.3@2 line map-connection 0 0 100 0 endline endscrap I'll create an issue in GitHub. Bruce