When moves are made the balance of power on the board can be shown with arrows. This can be selected by the menu Training - Dynamic Hints.

Possibilities for attack and defence manoeuvres are shown when you press the mouse button over a piece or start dragging it. This effect gives assistance in understanding the balance of power on the board.
This information is shown in two colours. Green arrows are defensive manoeuvres, red arrows are attacks.
There are further differences shown by the type of line. A solid line shows a direct attack or defence. Dashed lines show a possible attack or defence that depends on the next move made.
If a red line is drawn thicker it is a move that will win material.

This means that the Dynamic Hints can be an effective help during a move by showing what consequences there will be on the board.