gMS Tespia Was a challenge to Odin?

You're kidding right?...

Facebook -> Free advertising -> they want people to see it and join maple-> Achieved by making the game look fun.

And screenshots of testing would help that more than what they've put up, how?

Nevermind for that. Still, probably, those screenshots were taken in Tespia, if it can matter anything.

All I'm saying is that Nexon said they'll release Tespia in the future again.

But the website has been taken down.

I doubt that they're actually going to release Tespia after seeing how much time has passed since the Open Letter. If they wanted they could've opened Tespia already, but they still haven't, and there is no known reason for them to not do it.