I believe at thei point you need to open a new map, and set a start marker, Run test game.
Press TAB twice. Change the terrain style. press TAB again, and then press ESC to go back to the editor. That should do it. For now that is not an option, but is now on the requested features list.
I would save that blank map as a template to use for starting new levels.
Not perfect, but does work.
any other questions, just let me know.
Thanks
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