Hi Therion Mailing list, I'm struggling with something after a surveying trip on Saturday (I've drawn everything up) but now want to strip the survey into lower and upper sections. At present I can run the top level .th file and stripped down config file to get the survey tree out (so I could select surveys individually at a lower level). However when I'm trying to use the code used in the Therion samples [installed on download]. therion/samples/map-offset/thconfig.4 it doesn't work. Please find below my error message, .th and config files, does anyone know where i'm going wrong? Error message calculating basic statistics ... done processing extended elevation ... done processing references ... C:\Program Files (x86)\Therion\therion.exe: error -- Fingernailviatpvtovortex2.th [9] -- object does not exist -- TotalperspectivevortM writing xtherion file ... done C:\Program Files (x86)\Therion\therion.exe: warning -- error deleting temporary directory -- C:\Users\alastair\AppData\Local\Temp\th27304 .th survey Fingernailviatpvtovortex2 input Totalperspectivevort/Totalperspectivevort.th input Totpersfromfinger/Totpersfromfinger.th input Vortex2/Vortex2.th map tpv TotalperspectivevortM break Vortex2M endmap map lower TotpersfromfingerM endmap centreline equate 1.7@Vortex2 1.2@Totalperspectivevort equate 1.0@Totalperspectivevort 1.6@Totpersfromfinger endcentreline endsurvey Config file source Fingernailviatpvtovortex2.th source #!CODE map Fingernailtovortex2 tpv break lower [-0 30 m] below endmap #!ENDCODE endsource Regards, Alastair Gott. AlastairGott@hotmail.com, M: 07931779380.