The latest ONScripter-EN (onscripter-en-20091227) has some bugfixes and new features (like ‘m’ sound volume mute toggle), but mainly there’s a bunch of new ONScripter Tools and features for them. Take a look at the Releases page.
A major new addition to the archive conversion tools is the option of providing a file-matching rules file, which allows telling how many cells/alphas an image has for the purposes of doing cleaner image resizing. Look at this rules.txt for examples.
I’ll start providing rules files for various games on the Compatibility page as they become available (Umineko’s there already), so let me know if you get together a good set of file-matching rules for PDA-converting your favorite (O)NScripter games.