Gremnon opened the ticket and wrote:

Using nightly r13592 map editor, using the generate flat map tool with height set to 0, the map is offset - the raise land tool's spots show up off the westernmost corner in an area not normally useable, and trying to use it in the easternmost corner causes the game to crash with a runtime error on mapsize.

Reported version: 0.6.1
Operating system: Windows

This issue was imported from FlySpray: https://bugs.openttd.org/task/2106