I've found Tilesystem has some memory limitations. The Conan board game tilesystem editor has grown to incorporate more than 1000 images. This broke the JPG Export functionality (which is a major and very often used feature).
The solution was to divide the Conan editor into 2 tilesets. The first is the Map editor (conan.set) which contains all the Board, Features and Tokens used create maps for scenarios. The second is the Book of Skelos editor (skelos.set) which contains all the Overlord tiles and Tokens used to create the river and the overlord's book of skelos.
Since you can have multiple instances of Tilesystem open at the same time, this actually works out better for creating the images for scenarios.
Installation is the same, just extract the archive to where you would like Tilesystem installed. (This will not overwrite previous versions, so those will have to be deleted manually).
The updated editor can be found here: Conan Boardgame Downloads
NOTE 2022-09-06: v6.2 adds the character tokens to the skelos.set file.
Happy Creating!