FOSS gamedev and creative worlds

I noticed that sometimes my server will be in creative mode and sometimes not. Is there a way to control this so it will always be in creative mode or not?

Also how can i set the default starting location for new players?

To enable/disable creative mode add "creative_mode = false/true" to your minetest.conf, and you can set the starting location with "static_spawnpoint = x, y, z". Look through the minetest.conf.example, it has information on these and many other useful settings. The minetest.conf wiki page has more detailed information, but not for server-specific settings.