[BobCratchett]

I'm happy with it in Skin Shortcuts just because I'm using the 'Get More...' button of the select dialog to trigger the process, as that seems a natural place for it. That and I'm just so much more familiar with the Skin Shortcuts code I'm happy for it to be switched, though, if that's the prevailing opinion of where its best done.

I don't mind where the ctual code is, I know both projects prettu well in the meanwhile ;-)
It's just that I'm thinking about the logic to get this right...

I was thinking about the following... list all options. If a user clicks a addon that isn't installed, popup the Kodi default question if the addon should be installed.
That would require no special dialogs at all, just a query to the addonpath would be enough to trigger kodi with the question

Unless you're thinking of changing how the widgets are listed in skin helper to a hierarchical-by-addon list, that wouldn't work as - unless Library Data Provider, Extended Info & Smart(ish) widgets are installed, skin helper doesn't know what widgets they provide (as at the moment it gets the widget options directly from the widget provider when it caches them.) Split up hierarchically that could work - click on 'Library Data Provider widgets >' and Kodi asks you if you want to install it - but doing it that way would, I suspect, make it harder to skinners to decide how to arrange the various widget providers themselves as they can currently do...