A bug in UBT is preventing the authors of SkookumScript from submitting their 4.16 plugin to the marketplace.
Install 4.16.0 binary release
Extract the attached plugin to D:\SkookumScript
Run the following command from Engine\Build\BatchFiles in the binary release
runuat buildplugin -plugin=D:\SkookumScript\SkookumScript.uplugin -Package=d:\skookum -targetplatforms=Win64+Win32+Android -nocompile
Observe that the compilation prints out "WITH_EDITOR is 1 in SkookumScriptGenerator but should be 0!"
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-45393 in the post.