The simplest effect you can emit from custom content is generated text. To automatically insert text before or after your element contents type the required text into the Pre content or Post content fields. Any amount of text, from single characters to whole paragraphs, can be added this way.

If a section number needs to be printed in square brackets, then type [ into Pre content and ] into Post content of the section number tag mapping. The construction <secnum>11B</secnum> in the document will map to [11B] in the output.

If a part number is always preceded by "Part — " then type Part &mdash;<space/> into the Pre content field. Using <space/> instead of a space character (at the end of a line) ensures that the space is clearly visible when examining or editing the custom content.