Version 0.7.xxx and above break the SDK, as GH was updated to completely use the RhinoCommon. Subsequently, custom components no longer work with newer versions. It is up to developers to update their components so that they can be used with the newer versions.
I know you've described the new Escape abort as rudimentary, but when a Rhino command is exited with the Esc key, Grasshopper thinks the Esc press was applied to it upon the next Grasshopper edit.
Hmm, this is getting out of hand. We now have unique symbols for expressions, flattening, grafting and reparameterizing and Lord knows what else in the future. I'm starting to think it might be better to have just a single symbol for anything out of the ordinary and then additional information in the tooltips about what exactly is non-standard about the object.
Thanks a lot for the update. I think the point of having a symbol is to make other people aware (and yourself revisiting old definitions) that the parameter has been altered. A simple dot for anything out of the ordinary and the tooltip will do just fine.