The sugarglass is crafted using the sugar cauldron. Place it on top of a cooking furnace and boil some water in it. Place a block of sugar in it and after a few seconds it will turn into 16 pieces of sugarglass. Use that to create glass and/or colored panes and place accordingly.
The glass will break if fired at with any projectile. Unfortunately this destroys the block completely but that’s just the point of the mod.
And glass will also break from falling through it. So you can now recreate a dramatic skylight entrance by jumping down through the ceiling.
Thin ice is also something to be concerned about if you encounter it. It looks and acts like regular ice but if you step too forcefully or jump on it, you will most certainly fall through.