Anyway to get this into a windowed mode?

Do not have the game installed (long time ago played it), but have you tried Ctrl-Esc to see if that may work?
Maybe check options as well.

Doesn't seem to want to recognise the alt or ctrl buttons.
If I do alt-enter, it just accepts enter as if I selected something from the menu.
Similarly, pressing anything with esc makes it register esc as if I want to quit.

I would also like to know this. How can i play the game in a window?

You can try 2 things:
1) edit game shortcut's properties - in the Target field add: -w at the end
or
2) try using DXWnd
I hope this helps, but some games just won't run well (or at all) while windowed - Ground Control may be one of them.