[XODIDOX]

I don't think it should be interrupting library scans - either get the info from the file name or let the user input them later.

No problems for me.
 

Everything should disabled by default.

No problems for me. The current behavior for both were from the previous discussions on this thread.
 

When selecting a movie I think you should just open up the select dialog with images (list ID=6) for version selection.

Not sure I understand this.
 

The Versions dialog should only be used for managing versions and either opened via the conext menu or video information dialog.

Showing the dialog when playing a movie was special requested by Kodi team member on the initial discussion on this thread.
 

The Version dialog could IMO reuse the video information dialog - skinners hate having to add more dialogs.

I don't think mixing up totally unrelated things together is a good design.
 

The 'Versions' button in the video information dialog should only be enabled (ie visible) when there are versions available.

The dialog provides ways to add/remove/change versions, if only visible for movie with multiple versions, user need to use another way to manage versions.
 

In the Version dialog why don't posters work? Thumbs aren't very informative.

"videoversion" is a new media type, you can add whatever arts you want for it, and the UI uses thumbnail by default is because, as all of these versions are for same movie item, so they have the same poster by default, if we use poster by default, it's hard to see any difference between them without choosing arts manually. And thumbnail also works for extras. But this can be changed. I just thought thumbnail is most suitable here.
 

Extras should be a seperate thing.

Not sure what kind of separation here. They are in the separate list in the dialog.