Overhauls multiplayer spawning system. This mod serves one purpose. To serve the scenario files over the mod portal. The best source is the github page.
Scenarios, maps, and puzzles.
How do I download GitHub version and where do I put the files?
https://github.com/Oarcinae/FactorioScenarioMultiplayerSpawn
Instructions are in the wiki there: https://github.com/Oarcinae/FactorioScenarioMultiplayerSpawn/wiki
If you have more questions just ask.