Also, I wasn't able to figure out how to create a new file (the manual for "map" said you could) so I had to resort to editing the savefile to create the new script. I also don't remember Ctrl S being mentioned in the manual, but that might just be me. I was kinda confused at first when Ctrl R didn't enable the map correctly, then I went back and pressed Ctrl S for both src.map and src.config. Then it worked.
I’m glad you like the game! The last beta release was in 2017, so it’s really not under active development any more. I would like to pick it up again some day, but it might be a year or two before that happens. If it does, it’s quite likely that the API would change significantly. I have a branch where all the default in-game code is ported to Fennel instead of being written in Lua, though Lua is still available. We’ll see!