So I've been racking my brain on this one since yesterday afternoon and think I may have finally found at least something to get you pointed in the right direction.

I dug into the ModuleSettings control to see how it gets populated, and it comes from SkinControl, which pointed me to 

SkinController.GetSkins which takes a PortalInfo object, Skinroot (string, not sure what it really expects), and Scope.

Basically what this GetSkins method does is loop through the directory (this is likely what you pass in skinroot) /portals/_default/containers, or /portals/_default/skins or portal specific, and returns a listing.

My assumption is that eventually this method should look at the Extensions, but for the legacy support of non-DNN5 skins and containers it does it with the file based approach.

Hope that helps you somewhat.

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Chris Hammond
Former DNN Corp Employee, MVP, Core Team Member, Trustee
Christoc.com Software Solutions DotNetNuke Module Development, Upgrades and consulting.
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