Glad you liked it.

About sharing externally: Not at the moment sorry. 

I do plan to publish this as a standalone app with the option of adding the seed in the URL so you can either use the main URL for a randomly generated map, or  use a URL with seed so it'll always return the map specific to that seed. 

It's in my TODO list and will ping you once I publish a standalone app

Also, I'm curious... what's your use case of sharing it externally outside of Itch? Users don't have to be logged into Itch to see the map

Will help me prioritize my TODO list :-)