I am not familiar with all the fancy internal project at Digitalk, but
did use their older Smalltalk V/Win technology and found it very simple
and practical. The main image was a tiny "v.exe" file that got most of
the needed support objects and machine language code from a bunch of
".dll" files. As you worked on a project and saved the image. the v.exe
would grow and include essentially just wanted you had created yourself.
To ship it to other people, you would have also send along some support
.dll files but not most of them (the ones for the programming
environment).

Spoon also has multiple images and resources for moving things between
them.

This will be a major aspect of my work in the first half of this year,
by the way.

-- Jecel