That's how I understand what they wrote.

"Produce a new image:

  - Design a new Object Memory and image file format.

  - Alter the ST-80 System Tracer to write an image in the new format.

  - Eliminate uses of Mac Toolbox calls to restore Smalltalk- portability.

  - Write a new file system with a simple, portable interface."

Hmm...I wonder if Dan used the PDF writer I wrote for him to produce that version of the paper...

Thanks for the info. Hmm, it's kind of cool to think there might be a few classes in today's fully-accelerated-vector-graphics-morphic cuis system that were first keyed into the system on an Alto in the 70s :-)