At the right/bottom of the screen, there are six numbered squares: the trays. 

You can store pieces temporarily on the trays. For example, you could set a tray to hold all the pieces of the same color, or with a particular shape. It is possible to solve pieces in the tray. In fact, you can even solve the entire puzzle in a tray.

To put a piece into one of the trays open the tray and drag the piece into it.

There are several ways to open a tray:
- Pressing the number of the tray in the keyboard, for example pressing  1  would open the first tray,  2  the second one, etc.
- Double click over it when it is closed.
- Selecting the "Open" option in the tray's menu.

While the tray is open, you can drag pieces into it. Then you can close the tray again the same ways to open, either pressing its number in the keyboard, double clicking over the background of the tray or with the tray's menu (right clicking over a non occupied part).

A closed tray containing pieces appears on the screen in a raised shape filled with color to remind that there are pieces in it.

REMEMBER! If you don't find a piece, look to see if it's in some tray.

There is a fast way for sending pieces to trays: Point over the piece, hold down  Alt  and press the key number of the tray where you want the piece stored. To send pieces from a tray to the main desk press  Alt+Q  while pointing over the piece.

A tray can be moved, either the usual way clicking the title bar or Holding down  Ctrl , clicking and dragging.

The tray can be sized, as usual with any window, dragging its borders. It will not allow to set a size smaller than the area occupied by the pieces.

And a tray can be Maximized using the whole screen. Either use the tray's menu or press the key  Tab 

If the tray is open right clicking on the background will show its menu with these options:
 Scatter : To reorganize the pieces in the tray trying not to overlap if there is enough room.
 Empty : The pieces in the tray go to the main screen (except nailed pieces).
 Tray options : To configure some options in the trays.

In a closed tray, its menu has:
 Hide closed trays if empty : Makes the closed trays invisible if it contains no pieces.
It is a good option to have more room in the screen. Hidden the trays will still work, to open a hidden tray simply press the number (1 to 6) of the tray you want to open.
To make the trays visible again uncheck the option  Hide closed trays if empty   in the General Options window ( F3 ).