Several people have complained about lag since upgrading to V4. I've fixed this issue on my own machine, and now have several confirmations from others that the following process fixes the lag as well as some lag-related bugs (such as an autosort display error.)
1. Uninstall Ruby 1.9.1.
2. EDIT: Follow the new instructions at www.lichproject.com
Oh, and if you haven't already, download the new spell-list.xml.txt from the repository.
