If you want to avoid writing a lot of scenes, a custom library is the way to go. This will work well when invoked from the outside (via HTTP, so, no triggers).
Just add your code to VeraScenes.lua provide here. Remember to leave all your functions as public, if you want to call them. Upload the code via Vera's Web UI. Go to Apps, Develop apps, then Luup files and upload it.
In your startup code, just register the library:
VeraScenes = require("VeraScenes")
Then, when referring to the functions defined in VeraScenes, just use this:
VeraScenes.turnLightsOff()
This could be used via HTTP calls as well (via RunLua):
http://ip-address:3480/data_request?id=lu_action&serviceId=urn:micasaverde-com:serviceId:HomeAutomationGateway1&action=RunLua&Code=VeraScenes.turnLightsOn%28nil%29
NB: Be sure to encode your code via an online tool such as https://www.urlencoder.org/.