If we use Copy As AppleScript on double linear and radial fills:
We find that fills have blend color and blend fraction properties, and we can use the code to script the creation of similar fills.
tell application id "com.omnigroup.OmniGraffle6"
tell canvas of front window
make new shape at end of graphics with properties {blend color:{0.231373, 0.615686, 1.0}, blend fraction:0.548950195312, name:"Circle", fill:linear fill, textSize:{0.8, 0.7}, draws shadow:false, size:{130.715217, 130.715217}, origin:{94.284783, 310.284783}, textPosition:{0.1, 0.15}, vertical padding:0, fill color:{1.0, 1.0, 1.0, 0.829926}}
end tell
end tell
This fails, however, with fill blend types and distortion effect types.
