I just released PackRat 1.7. This release addresses the issues I had with releasing a Universal version that fixed the image issues. Now PowerPC users can get the fix as well. Intel users will want to get the update as well as pages are now displayed much faster.
Technically, I had to write a Textile converter and a template engine in Cocoa so I could remove RubyCocoa. RubyCocoa was the culprit that was keeping me from building a 10.4 universal version of the app. This is also why the page rendering is faster.
You can get the new version here.