Today a new update has been released!
Now there is a settings menu where you can adjust the game volume and also set shortcuts to select tools
The game volume can be set from a range of 0 - 10. 10 is default.
Key bindings means that if you press a given key then you automatically select the bound tool. Just go to the settings menu and click on a key entry and then select the desired tool from the dropdown menu. The keys are 0 - 9 on your keyboard (not the num pad, but you might adjust that in the keys.txt config file). This feature is helpful when you want to instantly switch between tools.