(Note : I do not know if there is a specific way to report bugs, I have done my best to give as much information as possible)
BUG : When shrinking the map with sandbox tools while the game is paused, game may start spamming the "Construction not possible while game is paused" error with the corresponding sound effect, resulting in loud constant noise and game freezing completely. This does not happen in the scenario editor (which, unsurprisingly, does not have a pause button).
GAME VERSION : v0.2.2 (298c9f5)
STEPS TO REPRODUCE :
Open the game.
Open any map containing objects (e. g. any scenario or saved game with progress). I've tested on "Build you own Six Flags park", "Six Flags Belguim" and "Carzy Castle" maps. The map's objects (trees, decorations, paths...) should preferably be close to its borders.
Pause the game.
Make sure the "Allow construction while paused" cheat is disabled.
Enable sandbox mode.
Open the map menu to access map editing tools.
Recommended before next step : Lower your volume (yeah, I jumped when it happened to me the first time)
Reduce the size of the map several times. It can go normally until the game has to delete a tile which has an object on it, in which case it will attempt to delete the object, causing the "Cannot build while game is paused" error and, apparently, making the game retry to delete the object again and again, resulting in a spam of the error's sound effect and in a complete game freeze. The game may or may not have had the time to display its last words in its ultimate render frame before it freezes : "Can't construct this here... Construction not possible while game is paused!"
TEMPORARY FIXES :
Make sure the "Allow construction while game is paused" cheat is enabled
Do not pause the game while shrinking the map
Clean the map's edges before shrinking it