Ooh, this is such a cool idea! I hope you do end up working on it more-- I'd be particularly interested in WASD support. Great job!
Having now played it (and loving it), I see WASD is included by default. Yay! I did find a pretty hefty bug-- I was placing floor tiles, and wanted to place one beneath the stairs-- silly, I know... but it covered the stairs down, and I then wasn't able to use that tile anymore.
And a smaller problem (or maybe intended), I can't pick up tiles after I place them.
Thanks for all your hard work!
On the plus side! You can't save without going down the stairs so next time you reload the game the stairs will be back? And yeah at the moment we're not implementing picking up tiles you've placed because it introduces some very weird gameplay logic questions.
And WASD was added in the last update because you requested it so I'm glad it's bringing you joy. :)