Using Slow Chess in Own GUI:

If it's your turn and you click on one of your pieces, it will be selected, and a white box appears around it. Then just click where you want to move it, or drag and release on the destination square.
Castling is done by clicking the king, then the square where he would end up after castling. (FRC is an exception, to castle click the rook square after the king. Otherwise can be ambiguous.)
En Passant captures are performed by clicking the pawn and then its destination square.

Move button: Tells the computer to stop thinking and play the best move its found so far if it's thinking, otherwise it will tell the computer to start playing as the side to move.
Retract button: will take back the players last move so that he can make a different one.
< and > : will move a half a move backward/forward respectively.
<| and |> :will go to the first and last move of the game.
Clicking on the transcript will set the board to the move clicked on.

The Difficulty level uses all limits set. (Let's say it's set to 7 ply, 5 seconds. If it completes a 7 ply search before 5 seconds it will stop, otherwise it will stop after 5 seconds no matter how far it has searched.) The 52 ply is meant to be used for time based games, since it will always (except certain endgame situations) reach the time limit before it reaches 52 ply. Seconds per move defaults to 0, and when it's set to zero it uses the time control to choose how long to think about its next move, instead of thinking a set amount of time per move. 

Analysis: To start analysis of the position currently on the board, click the "Analyze" button in the side window. A window will appear below the board which will display the principle variation of the best move or best moves found. If you don't mind much slower best move analysis, you can use the '+' and '-' button to have the computer calculate the 2nd best-6th best moves in addition to the best. You can also turn on the analysis window while playing against the computer from the options menu.

Multi-Threaded search: The default is 1 thinking thread. For better and quicker analysis, you can increase this number under Search->Threads. This setting is saved in the EngineGUI.dft file. More threads is only a benefit up the the actual number of hardware threads your CPU supports, and additionally you might not want to use the hardware max threads or other programs might become sluggish.

Displayed Search Info: When the computer is thinking, it will display info about the search unless this option is unchecked. It will display the furthest depth to which it searched a move completely (with a * afterwards if not all moves were searched to that depth, a * after the eval value means there's no value for this move at the current depth), the number of nodes it searched, and search speed in Kilonodes/sec, and the evaluation value of the best move.

In the window beneath a player's time, 1R, 2p beneath black's time would mean that black has 1 more rook than white, and 2 more pawns.
The large print top clock is the time left for a player to complete his move (according to the time limit set on the menu.) The bottom is the total time the player has taken to make his moves so far. If the time left runs out, you would lose the game by the rules of chess, but in this program your clock just stays at zero and you're free to continue to play.

Note on the opening book: You manually add or remove positions from the opening book with the 3 and 6 keys. (Also 1 or 2 keys = position prefered by black. 4 or 5 keys = position prefered by white.) Remember to Save the book when you're done, it never autosaves. You can also add .pgns to the book. If you load an opening book the positions will be added to whatever is in the book in memory. Slow Chess can't handle really large books. 

Interested in how Slow Chess evaluates the board? Right-Click on a piece to see it's full evaluation breakdown. Develop->Display Eval to see total board evaluation.

Using Slow Chess as a Winboard Engine:

• The same slow64.exe can be used as a winboard or UCI engine in any interface that supports those protocols.
• Winboard settings are all saved in engineWB.dft.
• You can set the winboard settings from the Slow GUI using Options->Winboard Settings, or by directly text editing the save file engineWB.dft.
• The transposition table size is additionally settable from command line with -TT128 where 128 is the size in MBs.
• Note : actual TT size will always be a power of 2. So 64, 128, 256, etc.
• On startup it will try to load the endgame bitbases and opening book, expecting same directory structure as in the downloaded. zip.
• Own Opening Book usage can be turned off in winboard settings. Under UCI it's the ownBook UCI option.
• Slow Chess saves its games under winboard to winboardgames.pgn in the directory it is run (can be turned off in winboard settings.)
• FRC / Chess960 variant supported under UCI but not tested under Winboard.

• supports multi-threaded search, respecting the winboad cores command. Settable in WinBoard under "Options->Common Engine->Max nr of CPUs"
• If there exists a winboard GUI that doesn't send the cores command, the default is set by "Threads=#" in engineWB.dft
• UCI multi-threading uses the "Threads" setting in engine options.

Slow.exe can be used as a winboard engine the same way as any other. Slow Chess only supports protocol #2, it doesn't support older winboard versions. Versions 2.93a and later also support UCI. Because it makes things much simpler for me to have only 1 .exe to update, I don't have a separate console winboard version.  The only thing I've noticed because of this is there's an hourglass next to the cursor upon startup for a few seconds. Also note that For those who like to know the country of their winboard engines, Slow Chess' official country of origin is the United States.

Known issue : On some computers, the Fritz GUI doesn't doesn't display the thinking lines until much later than they are received. This seems to be a problem particular to the Fritz GUI and happens to many other multi-threaded winboard/UCI engines. Checking the Slow Chess UCI option "Low Priority" should fix this, I don't know if this option will affect anything else.