Thanks for trying it out! Hopefully these explanations help you, if not, please let me know.
1. Depending on the board constellation, there can be multiple different chunks which can be moved. For example, first row all black, second all white, third all black. The game ends when you remove a block where all tiles are the same color. So in this example, removing the white row would get you closer to that state.
2. Yes, when there are multiple directions towards which you can remove a chunk, it doesn't matter which one you choose.
3. In general, only the removed tiles are refilled. However, when this leads to a board with no possible move, e.g., like a chessboard pattern, the whole board gets replaced immediately.
1. Depending on the board constellation, there can be multiple different chunks which can be moved. For example, first row all black, second all white, third all black. The game ends when you remove a block where all tiles are the same color. So in this example, removing the white row would get you closer to that state.
2. Yes, when there are multiple directions towards which you can remove a chunk, it doesn't matter which one you choose.
3. In general, only the removed tiles are refilled. However, when this leads to a board with no possible move, e.g., like a chessboard pattern, the whole board gets replaced immediately.