1. Create a collection with the maps/content you want (http://pingperfect.com/phpbb/viewtopic.php?f=9&t=1339)
2. Create a custom command line in the game panel with the following fields filled out -Authkey, +gamemode, +map, +host_workshop_collection, +map, +exec
3. Authkey should be set to your API key you generated in step 1, gamemode/gametype/map/mapgroup/workshop start map are down to what you want, host workshop collection is the collection ID you created in step 1
4. Save the command line and select it and your server is now running with workshop content.
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