Minetest is an "open source voxel game engine and game. Fully extendable. You are in control." Check out www.minetest.net for more information.
The Basic (free) plan is there to allow people to try out MinetestHosting.com, it isn't intended to be a full featured exprience, otherwise no one would ever pay for it. Check out our paid plans and all of the cool feature that they include.
Servers hosted on MinetestHosting.com are setup to go to "sleep" when they are empty for a while. This allows us to run many servers on a smaller number of physical boxes, by only allocating resources to servers that are active. As soon as someone tries to connect to your server it will "wake up" and accept the connection.
We have had a few instances of people who are spawned deep under ground. Try either digging your way out or grant fly and noclip privilages so you can fly out of the ground.