Forum thread for the OSP author @SendMeSmile, indexing a MBRepository file (the author can have the thread reattributed to him on request should he become active again).
How to install...
Copy all to your module folder. For example to C:\Program Files\Mount&Blade Warband\Modules\Native.
Open module.ini find and change line: load_resource = skyboxes to load_mod_resource = skyboxes.