Woah, 11 hour stream, awesome!
Sorry about the scroll wheel, we had accessibility options planned for full keyboard control but only got partially there. You can move the hand(s) with WASD and use Q and E to select the hand. No button yet for the scroll wheel, other than using a controller.
We would love to add multiplayer in a future version, time was too short to experiment with multiplayer for too long.
Thanks for playing!