After far more pain and hardship than I ever thought it would require, and pretty much the entirety of the past two weekends, I've finished refactoring the entire find/replace system for KJots. It now supports every kind of find/replace option generally available, including regexps and placeholders during replaces. And yes, you can also recursively search and replace all pages in the bookshelf, with or without a cute little Replace/Skip/All/Cancel dialog box if you wish to have one.