does current build only run in windowed mode?

hi everyone:
I tried using the searching box to find similar threads I found nothing, I would like to ask if current build(49167) only runs in windowed mode?
thanks

on top of that:
During one game my commander first went underground and later went above the ground floating in air and getting higher and higher.

I haven't seen any option to go into full screen mode unfortunately, so I think for the time being it is windowed mode.

Units going underground is a confirmed bug on the bug tracker, just need to wait for a new build that address it (not necessarily the next one).

I saw an "Ant Tank" go though water, that did not seem right.

Yes.

No full screen option and alt+enter doesn't work either.

So I definitely say YES.