It should never have got to this situation in the first place. I've been in this Alpha since day one and hacker problems have worsened daily. "Yeah it's Alpha dude" but it's also open source and should have been envisaged by someone.
PS what is Steam doing about this ? and if the answere is "nothing" what is the point of Steam unless its just there as another retail outlet for an unplayable, albeit Alpha release game. I remember good old days when you didn't have to pay to help out the developers you used to get invited