the idea behind the Play-Test Applet is that it would make things as easy as riding a bicycle, where otherwise they are as complex as assembling your own car from parts, and learning how to drive it.
That's not quite correct. The alternative to using the Play-Test Applet will often just involve copying a preset that already works, writing FEN code for the board, assigning piece labels and notation to the correct pieces, and saving. As long as a game uses pieces already programmed in the fairychess include file, has a fixed setup, and mainly follows the rules of Chess, it should be easy enough to create a programmed preset for it without knowing how to program.
That's not quite correct. The alternative to using the Play-Test Applet will often just involve copying a preset that already works, writing FEN code for the board, assigning piece labels and notation to the correct pieces, and saving. As long as a game uses pieces already programmed in the fairychess include file, has a fixed setup, and mainly follows the rules of Chess, it should be easy enough to create a programmed preset for it without knowing how to program.