click: add voxel, shift + click: remove voxel. use color selector to change block color
click: Position cube
Drag handles: Resize cube
click on buildplate: Finalize cube
click outside buildplate: Cancel cube
Use the color selector to choose color, and click blocks to change their color.
Check Variate to randomly change the brightness of colors.
Use the color selector to choose color. Click on a block to set all blocks matching its color to the selected color.