Hi, just wanted to drop a note that I just managed to compile the therionsurfac2survex tool also for mac now. You can use it to generate a surface mesh (legs with -flag surface) out of GDAL or therion surface files. This is useful if you for example want to measure distances from cave to surface with the help of aven. I updated the latest release with the binary: https://github.com/hbeni/therionsurface2survex/releases/tag/1.1.0 Have fun, and let me know if it works, Beni