Open space

A puzzle type I spotted at the 2015 WPC. It allows for quite spare clueing, but then it is very susceptible to uniqueness arguments.

Open space rules: Paint some empty cells black. Black cells share neither side nor corners. Clues indicate the sum of visible squares in the four cardinal directions, including the clue cell. Black cells and grid edges obscure sight.

The online solver is for Kuromasu: Consequently, all its' complaints are legal, but it will accept wrong solutions.