At the same time I received an e-mail from a reader asking if there was any way to play through games posted on this blog with Aquarium by using the arrow keys instead of a mouse. I couldn't answer that and suggested he contact ChessOK support which he did. He was informed that it was not possible, but he found an ingenious solution on his own that works with Windows 10; I am not sure about earlier releases. Thanks to Mr. Wijnand Engelkes of Holland here is how it's done.
1. Press (left) Shift, (left) Alt and the NumLock Key simultaneously.
This produces a window that asks "Do you want to turn on mouse keys?"
2. When you answer yes this changes the numeric keyboard.
You then cannot use it anymore (until switched off) for typing 1,2,3, etc., but 8 will move the mouse cursor up, 4 left, 6 right, 2 down. And the only one you need is 5 which will produce a left mouse click. The normal mouse keeps responding, so now you have two mice.
From now on, you can press numeric "5" to move one half-move ahead. When you press (left) Shift, (left) Alt and the NumLock Key again the numeric keyboard works as before. In the Windows Accessability options for the mouse you can change the speed of the emulated mouse.