Even if you create custom layout you still need to define the used fonts by the epub. You can do this with the following code:
@font-face {
font-family: Prophecy Script;
font-style: normal;
font-weight: normal;
src:url("Fonts/Prophecy_Script.ttf");
}
Once you complete this, you need to apply it to your book:
p.letter {
font-family: "Prophecy Script";
font-weight: normal;
font-style: normal;
font-size: 1em;
margin: 1em 0 0 0;
-webkit-hyphens:none;
}
You will also need to define the area with the following handle: <p class="letter">Test</p>. On the other hand, custom fonts need to be enabled in the **com.apple.ibooks.display-options.xml**. The line should be like this: **<option name="specified-fonts">true</option>**.