The shuffle parameter has nothing to do with promotion; it defines how the initial setup has to be shuffled each time you start a new game, like in Chess960. Mentioning only a single piece type there has no effect. For promotionChoice you can give a list of all pieces the user can choose from when a Pawn promotes. The choice will have to be made when you move the Pawn into the zone, by clicking the desitred piece in the piece table (where available choices will be highlighted in blue). For normal Chess you would have to set it to QRBN. (Or Q,R,B,N ; it understands comma separation, which can be needed when some of the pieces have multi-letter ID.) But if you specify nothing it will assume all piece types in the initial setup except Pawn and royal.
There is a difference between the Play-Test Applet and the Interactive Diagram on which the Play-Test Applet is based. The Diagram supports many more options than those you can specify through the Play-Test Applet. The latter is a compromise between easy operation for the most common cases and versatility. In particular the Play-Test Applet assumes chess-style promotions: a single Pawn type promotes on reaching a certain rank, and the user can then choose between a number of piece types. The Diagram supports a parameter maxPromote, which can be used to specify the number of piece types that can promote. But the Play-Test-Applet automatically sets that to 1, and offers no method for the user to alter it. Even if it could be altered, it would assume all the promoting types have the same choice for the piece to promote to.
It sounds like what you want is more like a shogi-style promotion, where there is no choice (other than to promote or not), but each promoting piece type has a fixed type to which it promotes. The Diagram also supports that, through a parameter promoOffset, which would cause all promoting types to be upgraded that number of rows in the table on promotion. So which type promotes to what is then critically determied by the order of the pieces in the table. The Play-Test-Applet does not have a method to let the user specify promoOffset, and offers no control over the order of the piece types in the table (which is just inherited from the table you select the pieces from). This is mainly because I have no good idea for how to let the user specify that in an easy way (especially the order).
If you want to make the full power of the Interactive Diagram available, rather than just what the Play-Test Applet allows you to specify, the only possible course of action is to create your own web page with an Interactive Diagram (which could be on your local computer), and than edit the Diagram specification by hand to use the features that the Play-Test Applet doesn't allow you to set or alter. You can start by using the Play-Test Applet to get as close to the desired rules it allows, and then use the button at the bottom of the page to create the HTML for the Diagram. Which you could then paste into the HTML page you are making. (If you put that page not on the CVP website, but elsewhere, such as on your local computer, you would have to prefix the links it contains with http://chessvariants.com to make it work.) You then have the possibility to edit the Diagram specification in any way you want.
You could of course paste the Diagram you are working on into a comment here, submitting it in HTML mode (as Daphne did below).
The shuffle parameter has nothing to do with promotion; it defines how the initial setup has to be shuffled each time you start a new game, like in Chess960. Mentioning only a single piece type there has no effect. For promotionChoice you can give a list of all pieces the user can choose from when a Pawn promotes. The choice will have to be made when you move the Pawn into the zone, by clicking the desitred piece in the piece table (where available choices will be highlighted in blue). For normal Chess you would have to set it to QRBN. (Or Q,R,B,N ; it understands comma separation, which can be needed when some of the pieces have multi-letter ID.) But if you specify nothing it will assume all piece types in the initial setup except Pawn and royal.
There is a difference between the Play-Test Applet and the Interactive Diagram on which the Play-Test Applet is based. The Diagram supports many more options than those you can specify through the Play-Test Applet. The latter is a compromise between easy operation for the most common cases and versatility. In particular the Play-Test Applet assumes chess-style promotions: a single Pawn type promotes on reaching a certain rank, and the user can then choose between a number of piece types. The Diagram supports a parameter maxPromote, which can be used to specify the number of piece types that can promote. But the Play-Test-Applet automatically sets that to 1, and offers no method for the user to alter it. Even if it could be altered, it would assume all the promoting types have the same choice for the piece to promote to.
It sounds like what you want is more like a shogi-style promotion, where there is no choice (other than to promote or not), but each promoting piece type has a fixed type to which it promotes. The Diagram also supports that, through a parameter promoOffset, which would cause all promoting types to be upgraded that number of rows in the table on promotion. So which type promotes to what is then critically determied by the order of the pieces in the table. The Play-Test-Applet does not have a method to let the user specify promoOffset, and offers no control over the order of the piece types in the table (which is just inherited from the table you select the pieces from). This is mainly because I have no good idea for how to let the user specify that in an easy way (especially the order).
If you want to make the full power of the Interactive Diagram available, rather than just what the Play-Test Applet allows you to specify, the only possible course of action is to create your own web page with an Interactive Diagram (which could be on your local computer), and than edit the Diagram specification by hand to use the features that the Play-Test Applet doesn't allow you to set or alter. You can start by using the Play-Test Applet to get as close to the desired rules it allows, and then use the button at the bottom of the page to create the HTML for the Diagram. Which you could then paste into the HTML page you are making. (If you put that page not on the CVP website, but elsewhere, such as on your local computer, you would have to prefix the links it contains with http://chessvariants.com to make it work.) You then have the possibility to edit the Diagram specification in any way you want.
You could of course paste the Diagram you are working on into a comment here, submitting it in HTML mode (as Daphne did below).